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研究生: 郭仁皇
Kuo, Jen-Huang
論文名稱: 氧金屬催化親和性醯基取代反應與酯基交換反應
Nucleophilic Acyl Substitutions of Anhydrides and Esters eith Protic Nucleophiles Catalyzed by Water Tolerent, Amphoteric, Oxometallic Species
指導教授: 陳建添
Chen, Chien-Tien
學位類別: 博士
Doctor
系所名稱: 化學系
Department of Chemistry
論文出版年: 2004
畢業學年度: 92
語文別: 中文
論文頁數: 223
中文關鍵詞: 催化氧金屬親和性醯基取代反應酯基交換反應兩性特質水相安定
英文關鍵詞: Nucleophilic Acyl Substitutions, Protic Nucleophiles, Oxometallic Species, Amphoteric, Water Tolerent, Catalyzed
論文種類: 學術論文
相關次數: 點閱:198下載:10
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  • 中文摘要
    在實驗過二十四種不同的氧金屬催化劑後,發現對於親核性醯基取代反應上,三氟甲磺酸氧釩(VO(OTf)2)、正六價二氯化雙氧鉬 (MoO2Cl2)和正六價四氯化氧鉬(MoOCl4)三者為最有效的催化劑。針對一系列的親核試劑如醇類、胺類以及硫醇類來說,上述的催化劑可以達到高化學產率以及高化學官能基的選擇性。眾所週知,氧鉬金屬對於氧化反應已有完整的研究。然而,對於親核性醯基取代反應而言,氧鉬金屬催化劑在具有多種官能基團的化學環境裡仍保有高安定的特性則是催化反應中空前的新發現。
    我們進一步利用苯甲酸酐為媒介,針對各種官能基化的酸類化合物生成混合酸酐,可以將親核試劑進一步修飾為油酸酯(oleate), 雙肽(dipeptide),雙苯基甲基衍生物(diphenylmethyl),N-9茀甲氧羰基-α-胺基酸衍生物(N-Fmoc-α-amino),丙酮醯基衍生物(pyruvic),第三丁基硫酯衍生物(tert-butylthio ester),第三丁基醯胺衍生物(N-tert-butylamide)和三芳香基甲基衍生的丙烯醯基酯類(trityl acrylate)等官能化產物。另一方面,我們利用核磁共振光譜(NMR)與電灑式質譜儀(ESI-MS)的動力學實驗得知,在親核性醯基取代反應上,相較於之前本實驗室所發表的氧釩金屬催化劑而言,鉬和釩兩金屬對於氧金屬中心的兩性特質與行為具有高度的相似性。

    英文摘要
    Among twenty-four different oxo-metallic species examined, vanadyl triflate, dioxomolybdenum dichloride and oxomolybdenum tetrachloride were the most efficient catalysts to facilitate nucleophilic acyl substitution (NAS) of anhydrides with a myriad array of alcohols, amines, and thiols in high yields and high chemoselectivity. The catalytic NAS tolerates virtually all kinds of functional groups and was unprecedented in view of the well-recognized redox chemical behaviors associated with oxomolybdenum (VI) species. By using benzoic anhydride as a mediator for in-situ generation of an incipient mixed-anhydride with a given functional alkanoic acid, one can achieve oleate, dipeptide, diphenylmethyl, N-Fmoc-α-amino, pyruvic, and tert-butylthio ester, N-tert-butylamide and trityl acrylate syntheses with appropriate protic nucleophiles. Similar to vanadyl species, the amphoteric character of the Mo=O unit in oxomolybdenum chlorides was proven by 1H NMR kinetic experiments to be responsible for the catalytic NAS profile.

    目錄 中文摘要 英文摘要 第一章 :緒論 3 第一節、前言 3 第二節、文獻研究 6 1-2-1、路易士鹼催化 6 1-2-2、布忍斯特酸與路易士酸催化 10 1-2-3、N - Heterocyclic Carbene催化 14 1-2-4、醇類與酸類化合物直接縮合反應 15 1-2-5、酯基交換反應 16 1-2-6、TMS triflate催化 17 1-2-7、Metal triflates催化 17 1-2-8、金屬過氯酸鹽類(perchlorates)化合物催化 23 1-2-9、固相催化劑 24 第二章、氧金屬錯合物催化酸酐類的親核性醯基化取代反應 26 第一節、背景、重要性及目標 26 2-1-1、氧釩金屬錯合物的兩性特質 26 2-1-2、其他氧金屬物質 32 第二節、結果與討論 33 2-2-1、氧金屬化合物的效應 33 2-2-2、溶劑效應 38 2-2-3、催化劑水相安定的特性 39 2-2-4、酸酐的效應 40 2-2-5、質子性親核試劑的效應 44 2-2-6、官能基的共存性試驗48 2-2-7、化學位向選擇性 52 2-2-8、苯甲醯基化反應的探討 53 2-2-9、混合酸酐的研究 56 2-2-10、反應機構的探討 61 2-2-11、多官能基化合物的應用 78 2-2-12、結論 79 第三章、以TiO(acac)2催化酯基交換型的親核性醯基取代反應 81 第一節、緒論 81 3-1-1、背景介紹 81 第三節、結果與討論 83 3-3-1、氧金屬催化劑的效應 83 3-3-2、溶劑效應 87 3-3-3、催化劑量的效應 88 3-3-4、酯類效應 89 3-3-5、親核試劑效應 92 3-3-5-1、醇類 92 3-3-5-2、胺類 94 3-3-5-3、醇類與胺類之官能基化學選擇性 96 3-2-5-4、硫醇類 97 3-3-6、以VO(OTf)2行酯基交換反應 98 3-3-7、酯基交換反應機構的研究 99 3-3-8、有機酸與甲酯之比較反應 101 第四節、結論 102 第四章、未來展望 103 參考文獻 108 第五章、實驗步驟及光譜數據 134 第一節、 分析儀器 134 第二節、 親核性醯基化取代反應實驗步驟及光譜數據 136 5-2-1、一般醯基化反應實驗步驟 136 5-2-2、催化劑回收的實驗步驟 136 5-2-3、反應機構研究的實驗步驟 204 5-2-4、核磁共振光譜之動力學解析實驗 206 第三節、酯基交換反應實驗步驟及光譜數據 209 5-3-1、一般酯基交換反應實驗步驟 209 5-3-2、參考文獻 229 附錄:1H NMR光譜圖 13C NMR 光譜圖 NMR 動力學追蹤圖 ESI-MS動力學追蹤圖 反應的速率常數

    參考文獻:
    ( ) Greene, T. W.; Wuts, P. G. M. Protective Groups in Organic Synthesis, 3rd ed.; John Wiley & Sons: New York, 1999.
    (2) (a) Rowan, S. J.; Cantrill, S. J.; Cousins, G. R. L.; Sanders, J. K. M.; Stoddart, J. F. Angew. Chem. Int. Ed. Engl. 2002, 41, 898. (b) Karan, C.; Miller, B. L. Drug Discovery Today 2000, 5, 67.
    (3) Larock, R. C. In Comprehensive Organic Transformations, VCH Publisher Inc.: New York, 1989, 980.
    (4) For DMAP, see: (a) Hofle, G.; Steglish, V. Angew. Chem. Int. Ed. Engl. 1969, 8, 981. (b) Grondal, C. Synlett 2003, 10, 1568-1569. For functionalized DMAPs, see: (c) Wayman; K. A.; Sammakia, T. Org. Lett. 2003, 5, 4105. (d) Kurahashi, T.; Mizutani, T.; Yoshida, J. Tetrahedron 2002, 58 (43), 8669-8677. For leading references of phosphines, see: (e) Vedejs, E.; Bennett, N. S.; Conn, L. M.; Diver, S. T.; Gingvas, M.; Lin, S.; Oliver, P. A.; Peterson, M. J. J. Org. Chem. 1993, 58, 7286. (f) Vedejs, E.; Diver, S. T. J. Am. Chem. Soc. 1993, 115, 3358. For proazaphosphatrane, see: (f) Verkade, J. G.; Ilankumar, P. J. Org. Chem. 1999, 64, 9063. (g) D’Sa, B.; Verkade, J. G. J. Org. Chem. 1996, 61, 2963.
    (5) For HClO4/silica gel, see: (a) Chakraborti, A. K.; Gulhane, R. Chem. Commun. 2003, 15, 1896. For MeSO3H/Al2O3, see: (b) Sharghi, H.; Sarvari, M. H. Tetrahedron 2003, 59, 3627.
    (6) (a) Baker, R. H.; Bordwell, F. G. Org. Synth. 1955, 3, 141. (b) Chandrasekar, S.; Ramchander, T.; Takhi, M. Tetrahedron Lett. 1998, 39, 3263. For a review, see: (c) Chandra, K. L.; Saravanan, P.; Singh, R. K.; Singh, V. K. Tetrahedron 2002, 58, 1369. (d) Zhang, Z.; Yang, Z.; Wong, H.; Zhu, J.; Meanwell, N. A.; Kadow, J. F.; Wang, T. J. Org. Chem. 2002, 67, 6226. For the uses of N-acylbenzotriazoles and Lewis acids in acylation chemistry, see: (e) Katritzky, A. R.; Suzuki, K.; Singh, S. K.; He, H.-Y. J. Org. Chem. 2003, 68, 5720. (f) Katritzky, A. R.; He, H.-Y.; Suzuki, K. J. Org. Chem. 2000, 65, 8210. (g) Kumareswaran, R.; Gupta, A.; Vankae, Y. D. Synth.Commun. 1997, 27, 277.
    (7) Okano, T.; Miyamoto, K.; Kiji, J. Chem.Lett. 1995, 246.
    (8) Iqbal, J.; Srivastava, R. R. J. Org.Chem. 1992, 57, 2001.
    (9) (a) Grasa, G. A.; Kissling, R. M.; Nolan, S. P. Org. Lett. 2002, 4, 3583. (b) Nyce, G. W.; Lamboy, J. A.; Connor, E. F.; Waymouth, R. M.; Hedrick, J. L. Org. Lett. 2002, 4, 3587. (c) Grasa, G. A.; Güveli, T.; Singh, R.; Nolan, S. P. J. Org. Chem. 2003, 68, 2812. (d) Singh, R.; Kissling, R. M.; Letellier, M.-A.; Nolan, S. P. J. Org. Chem. 2004, 69, 209. For dialkyl imidazolium benzoates, see: (e) Murugesan, S.; Karst, N.; Islam, T.; Wiencek, J. M.; Linhardt, R. J. Synlett 2003, 9, 1283.
    (10) (a) Ishihara, K.; Nakayama, M.; Ohara, S.; Yamamoto, H. Tetrahedron 2002, 58, 8179. (b) Yamamoto, H.; Ishihara, K.; Ohara, S. Science 2000, 1140.
    (11) (a) Orita, A.; Tanahashi, C.; Kakuda, A.; Otera, J. J. Org.Chem. 2001, 66, 8926. (b) Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Am. Chem. Soc. 1995, 117, 4413.
    (12) (a) Ishii, Y.; Takeno, M.; Kawasaki, Y.; Muromachi, A.; Nishiyama, Y.; Sakagughi, S. J. Org. Chem. 1996, 61, 3088. (b) Orita, A.; Mitsutome, A.; Otera, J. J. Org. Chem. 1998, 63, 2420.
    ( 3) Otera, J. Chem. Rev. 1993, 93, 1449.
    (14) For LiClO4, see: Bartoli, G.; Bosco, M.; Marcantoni, E.; Massaccesi, M.; Rinaldi, S.; Sambri, L. Tetrahedron Lett. 2002, 43, 6331.
    (15) For Mg(ClO4)2, see: (a) Chakraborti, A. K.;Sharma, L.; Gulhane, R. S. Tetrahedron 2003, 59, 7661. (b) Bartoli, G.; Bosco, M.; Dalpozzo, R.; Marcantoni, E.; Massaccesi, M.; Rinaldi, S.; Sambri, L. Synlett 2003, 39.
    (16) (a) Chauhan, K. K.; Frost, C. G.; Love, I.; Waite, I. Synlett 1999, 1743. For a review on indium salt-promoted organic reactions, see: (b) Fringuelli, F.; Piermatti, O.; Pizzo, F.; Vaccaro, L. Curr.Org.Chem. 2003, 7, 1661. (c) Nakae, P.; Kusaki, I.; Sato, T. Synlett 2001, 1584. (d) Chakraborti, A. K.; Gulhane, R. Synlett 2003, 1805. (e) Kumaresvaran, R.; Pachamuthu, K.; Vankar, Y. D. Synlett 2000, 1652. (f) Li, A.-X.; Li, T.-S.; Ding, T.-H. Chem. Commun. 1997, 27, 277. (g) Kumar, P.; Pandey, R. K. Bodas, M. S.; Dongare, M. Synlett 2001, 206. (h) Ballini, R.; Bosica, G.; Carloni, S.; Kiarali, L.; Maggi, R.; Sartori, G. Tetrahedron Lett. 1998, 39, 6049.
    (17) (a) Procopiou, P. A.; Baugh, S. P. D. Flack, S. S.; Inglis, G. G. A. J. Org. Chem. 1998, 63, 2342. (b) Kumaresvaran, R.; Gupta, A.; Vankar, Y. D. Synth. Commun. 1997, 27, 277.
    (18) For Sn(OTf)2, see: (a) Mukaiyama, T.; Shiina, I.; Miyashira, M. Chem.Lett.1992, 625. For Tin (IV) porphyrin perchlorate, see: Tangestaninejad, S.; Habibi, M. H.; Mirkhani, V.; Moghadam, N. Synth. Commun. 2002, 32, 1337.
    (19) (a) Orita, A.; Tanahashi C.; Kakuda, A.; Otera, J. Angew.Chem.Int.Ed. 2000, 39, 2877. (b) Orita, A.; Tanahashi, C.; Kakuda, A.; Otera, J. J. Org. Chem. 2001, 66, 8926. (c) Peterson, K. E.; Smith, R. C.; Mohan, R. S. Tetrahedron Lett. 2003, 44, 7723. For a review of Bi (III) in organic synthesis, see: (d) Leonard, N. M.; Wieland, L. C.; Mohan, R. S. Tetrahedron 2002, 58, 8373. (e) Antoniotti, S. Synlett 2003, 10, 1566.
    (20) For TiCl(OTf)3, see: (a) Izumi, J.; Shiina, I.; Mukaiyama, T. Chem. Lett. 1995, 141. For TiCl4/AgClO4, see: (b) Miyashita, M.; Shiina, I.; Mukaiyama, T. Bull. Chem. Soc. Jpn. 1993, 66, 1516.
    (21) (a) Sarvanan, P.; Singh, V. K. Tetrahedron Lett. 1999, 40, 2611. (b) Tai, C.-A.; Kulkarni, S. S.; Hung, S.-C. J. Org. Chem. 2003, 68, 8719. For Cu(BF4)2, see: Chakraborti, A. K.; Gulhane, R. S. Synthesis 2004, 1, 111.
    (22) For Zn(ClO4)2-6H2O, see: Bartoli, G.; Bosco, M.; Dalpozzo, R.; Marcantoni, E.; Massaccesi, M.; Sambri, L. Eur. J. Org. Chem. 2003, 23, 4611.
    (23) (a) Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org.Chem. 1996, 61, 4560. (b) Ishira, K.; Kubota, M.; Yamamoto, H. Synlett 1996, 265.
    (24) Jarowicki, K.; Kocienski, P. Org. Synth. 1997, 454.
    (25) Dumeunier, R.; Marko, I. E. Tetrahedron Lett. 2004, 45, 825.
    (26) Le Roux, C.; Dubac, J. Synlett 2002, 2, 181.
    (27) (a) Maeda, Y.; Kakiuchi, N.; Matsumura, S.; Nishimura, T.; Kawamura, T.; Uemura, S. J. Org. Chem. 2002, 67, 6718. For oxidation of CH4 to actic acid or anhydrides, see: (b) Taniguchi, Y.; Hayashida, T.; Shibasaki, H.; Piao, D.; Kitamura, T.; Yamaji, T.; Fujiwara, Y. Org.Lett. 1999, 1, 557. (c) Zerella, M.; Mukhopadhyay, S.; Bell, A. T. Org. Lett. 2003, 5, 3193. For sulfoxidation of admantane to admantanesulfonic acid, see: (d) Ishii, Y.; Matsunaka, K.; Sakaquchi, S. J. Am. Chem. Soc. 2000, 122, 7390.
    (28) (a) Lattanzi, A.; Leadbeater, N. E. Org.Lett. 2002, 4, 1519. (b) Lattanzi A.; Senatore A.; Massa, A.; Scettri, A. J. Org. Chem. 2003, 68, 3691.
    (29) For a general review: (a) Hirao, T. Chem. Rev. 1997, 97, 2707. (b) For oxidative couplings: Hwang, D. R.; Chen, C. P.; Uang, B. J. J. Chem. Soc. Chem. Commun. 1999, 1207. (c) Hon, S.-W.; Li, C.-H.; Kuo, J.-H.; Barhate, N. B.; Liu, Y.-H.; Wang, Y.; Chen, C.-T. Org. Lett. 2001, 3, 869. (d) Barhate, N. B.; Chen, C.-T. Org. Lett. 2002, 4, 2529. For oxidative couplings of phosphonium salts, see: (e) Shi, M.; Xu, B. J. Org. Chem. 2002, 67, 294-297. For oxidative Mannich-Type coupling, see: (f) Hwang, D.-R.; Uang B.-J. Org. Lett. 2002, 4, 463. For vicinal dialkylation of cyclic enones: (g) Hirao, T.; Takada, T.; Sakurai, H. Org. Lett. 2000, 2, 3659.
    (30) For recent applications, see: (a) Belokon, Y. N.; North, M.; Parsons, T. Org. Lett. 2000, 2, 1617. (b) Ishii, Y.; Matsunaka, K.; Sakaguchi, S. J. Am. Chem. Soc. 2000, 122, 7390.
    (31) (a) Chen, C.-T.; Kuo, J.-H.; Li, C.-H.; Barhate, N. B.; Hon, S.-W.; Li, T.-W.; Chao, S.-D.; Liu, C.-C.; Li, Y.-C.; Chang, I.-H.; Lin, J.-S.; Liu, C.-J.; Chou, Y.-C. Org. Lett. 2001, 3, 3729. (c) See also: Wang, C.-C.; Luo, S.-Y.; Shie, C.-R.; Hung, S.-C. Org. Lett. 2002, 4, 847. (c) Chen, C.-T. US patent #: 6541659 B1, 2003. (d) Togni, A. Organometallics 1990, 9, 3106. (e) Schmidt, H.; Bashirpoor, M.; Rehder, D. J. Chem. Soc., Dalton Trans. 1996, 3865.
    (32) (a) Sheldon, R. A.; Kochi, J. K. “Metal-catalyzed Oxidations of Organic Compounds”; Academic Press: New York, 1981. (b) Mimoun, H. Angew. Chem. Int. Ed. Engl. 1982, 21, 734.
    (33) For the oxophilicity of Mo center in bidentate MoO2Cl2-(MeO(CH2)2O(CH2)2OMe) and MoO2Cl2 -DME complexes, see: (a) Kamenar, B.; Penavić, M.; Korpar-Čolig, B.; Marković, B. Inorg. Chim.Acta. 1982, 65, L245. (b) Dreisch, K.; Andersson, C.; Hakansson, M.; Jagner, S. J. Chem. Soc. Dalton Trans. 1993, 1045 and references therein. (c) Comprehensive Coordination Chemistry; Wilkinson, G.; Gillard, R. D., McCleverty, J. A. Eds.; Pergamon: Oxoford, 1987; Chapters 36.4, 36.5, 37, and 38. For the oxophilicity of Mo center in oxomolybdenum-calix[4]arene complexes, see: (d) Millar, A. J.; White, J. M.; Doonan, C. J.; Young, C. G. Inorg.Chem. 2000, 39, 5151. (e) Radius, U. Inorg.Chem. 2001, 40, 6637. For MoO2(O(CH2)2OMe)2 or MoO2(OCH2THP)2, see: (f) Lehtonen, A.; Sillanpää, R. Acta Chem. Scand. 1999, 53, 1078.
    (34) (a) Dreisch, K.; Andersson, C.; Stålhandske, C. Polyhedron 1993, 12, 303. (b) Dreisch, K.; Andersson, C.; Stålhandske, C. Polyhedron 1992, 11, 2143.
    (35) (a) Chisholm, M. H.; Folting, K.; Huffman, J. C.; Kirkpatrick, C. C. Inorg.Chem. 1984, 23, 1021. (b) Piarulli, U.; Williams, D. N.; Floriani, C.; Gervasio, G.; Viterbo, D. J. Chem. Soc. Dalton Trans. 1995, 3329. (c) Lang, R. F.; Ju, T. D.; Hoff, C. D.; Bryan, J. C.; Kubas, G. J. J. Am. Chem. Soc. 1994, 116, 9747.
    (36) (a) Holm, R. H. Chem.Rev. 1987, 87, 1401. (b) Stiefel, E. I. Inorg.Chem. 1977, 22, 1. (c) Young, C. G. In Biomimetic Oxidations Catalyzed by Transition Metal Complexes; Meunier, B., Ed.; Imperial College Press: London, 2000; Chapter 9, pp 415-459. (d) Collison, D.; Garner, C. D.; Joule, J. A. Chem. Soc. Rev. 1996, 25. (e) de Silva J. J. R. F.; Williams, R. J. P. “The Biological Chemistry of the Elements: The Inorganic Chemistry of Life”; 2nd Ed.; University Press: Oxford, 2001.
    (37) Direct uses of metal oxide clusters in neat acetic anhydrides in acetylations have been documented. For AlPW12O40, see: (a) Firouzabadi, H.; Iranpoor, N.; Nowrouzi, F.; Amani, K. Chem. Commun. 2003, 6, 764. For WO3-ZrO2 solid acid catalyst, see: (b) Reddy, B. M.; Sreekanth, P. M. Synth. Commun. 2002, 32, 2815. For CoW12O405 see: (c) Habibi, M. H.; Tangestaninejad, S.; Mirkhani, V.; Yadollahi, B. Synth. Commun. 2002, 32, 863. For Y5(Oi-Pr)13O and (thd)2Y(Oi-Pr) in acyl transfer of enol esters to alcohols, see: (d) Lin, M.-H.; RajanBabu, T. V. Org. Lett. 2000, 2, 997.
    (38) (a) TiO(OTf)2 and TiOCl2 were prepared by mixing TiO(SO4) with Ba(OTf)2 and BaCl2, respectively, in MeOH. (b) They are now commercially available from the institute, Clinigen and Bestgen Biotech.
    (39) (a) By following the procedure for making VOCl2 and NbOCl3 form VCl4 and NbCl5, respectively, we have synthesized the corresponding NbOCl2 from NbCl4 and ((CH3)3Si)2O, see: (b) Herrmann, W. A.; Thiel, W. R.; Herdtweck, E. Chem. Ber. 1990, 123, 271.
    (40) CrOCl4 is not available. Therefore, its catalytic behavior could not be evaluated.
    (4 ) TaOCl2 is so far not available. The extrapolated activity trend for the sixth period (Hf < “Ta” < W) is inferred from the trend observed in the fifth period (Zr < Nb <<Mo).
    (42) (a) Elmsley, J. Ed.; Clarendon Press: Oxford, 1991. (b) Zhang, C.; Schlemper, E. O.; Schrauzer, G. N. Organometallics 1990, 9, 1016.
    (43) Matsuda, Y.; Yamada, S.; Murakami, Y. Inorg. Chim. Acta. 1980, 44, L309.
    (44) The oxygenation of MoOCl4 occurs at ambient temperature. However, the similar reaction for WOCl4 proceeds at 100-120 oC, see: Gibson, V. C.; Kee, T. P.; Shaw, A. Polyhedron 1988, 7, 579.
    (45) For the preparation of MoOCl4 from MoO3 in refluxing SOCl2, see: (a) Taylor, J. C.; Waugh, A. B. J. Chem. Soc. Dalton Trans. 1980, 2006. (b) Diversi, P.; Ingrosso, G. I; Lucherini, A.; Landucci, M. Polyhedron 1987, 6, 281.
    (46) (a) For Lewis base character of Mo=O toward Br&oslash;nsted acids, see: Gibson, V.; Graham, A. J.; Ormsby, D. L.; Ward, B. P.; White, A. J. P.; Williams, D. J. J. Chem. Soc. Dalton Trans. 2002, 2597. (b) For Lewis acid character of Mo=O toward organosilanes, see: Kim, G.-S.; Huffman, D.; Dekock, C. W. Inorg. Chem. 1989, 28, 1279.
    (47) For the activation of molybdenum blue or MoO2(acac)2 by (Bu3Sn)2O to form (Bu3SnO)2MoO2, see: Kamiyama, T.; Inoue, M.; Enomoto, S. Chem. Lett. 1989, 1129.
    (48) For its uses in epoxidations, see: (a) Adam, W.; Mitchell, C. M.; Saha-M&ouml;ller, C. R. J. Org. Chem. 1999, 64, 3699. For reviews, see: (b) Herrmann, W. A.; K&uuml;hn, F. E. Acc. Chem. Res. 1997, 30, 169. (c) Romăo, C. C.; K&uuml;hn, F. E.; Herrmann, W. A. Chem. Rev. 1997, 97, 3197.
    (49) For the use of BiO(ClO4) as a catalyst for heteroatom acylation under solvent-free conditions, see: Chakraborti, A. K.; Gulhane, R. S. Synlett 2003, 12, 1805.
    (50) For the practical use of azido esters in click chemistry, see: Tornoe, C. W.; Christensen, C.; Meldal, M. J. Org. Chem. 2002, 67, 3057. (b) Rostovtsev, V. V.; Green, L. G.; Fokin, V. V.; Sharpless, K. B. Angew. Chem. Int. Ed. Engl. 2002, 41, 2596.
    (5 ) Basel, Y.; Hassner, A. J. Org. Chem. 2000, 65, 6368.
    (52) For one leading application, see: Barrett, A. G. M.; Hopkins, B. T.; Kobberling, J. Chem. Rev. 2002, 102, 3301
    (53) For leading applications, see: (a) Chen, Y.; Tian, S.-K.; Deng, L. J. Am. Chem. Soc. 2000, 122, 9542. (b) Jaeschke, G.; Seebach, D. J. Org. Chem. 1998, 63; 1190. (c) Bolm, C.; Schiffers, I.; Dinter, C. I.; Gerlach, A. J. Org. Chem. 2000, 65, 6984.
    (54) A retro Diels-Alder process was dominant when the reaction was performed at ambient temperature.
    (55) For enzymatic processes in warm media, see: de Gonzalo, G.; Brieva, R.; S&aacute;nchez, V. M.; Bayod, M.; Gotor, V. J. Org. Chem. 2003, 68, 3333.
    (56) (a) Costa, M.; Dalcanale, E.; Dias, F. S.; Graiff, C.; Tiripicchio, A.; Bigliardi, L. J. Organomet.Chem. 2001, 619, 2179. (b) Stauber, M. J.; Debiak-Krook, T.; Miller, M. J. Heterocycles 1993, 35, 1205. (c) Callahan, J. F.; Newlander, K. A.; Burgess, J. L.; Eggleston, D. S.; Nichols, A. Tetrahedron 1993, 49, 3479.
    (57) Felder, D.; Carreon, M. del P.; Gallani, J.-L.; Guillon, D.; Nierengarten, J.-F.; Chuard, T.; Deschenaux, R. Helv.Chim.Acta. 2001, 84, 1119.
    (58) A mixture of products was obtained under usual conditions (acid chloride/pyridine). For its effective acetylation mediated by TMSOTf, lower reaction temperature (-10 oC in ethyl acetate) was required (ref. 14).
    (59) Conventional procedures ((RC(O))2O/base) led to only pinacol rearrangement product.
    (60) (a) Ce(OTf)3: Dalpozzo, R.; Nino, A. De; Maiuolo, L.; Procopio, A.; Nardi, M.; Bartoli, G.; Romeo, R. Tetrahedron Lett. 2003, 44, 5621. (b) AlPW12O4: Firouzabadi, H.; Iranpoor, N.; Nowrouzi, F.; Amani, K. Chem.Commun. 2003, 6; 764. (c) Bi(OTf)3: Mohammadpoor-Baltork, I.; Aliyan, H.; Khosropour, A. R. Tetrahedron 2001, 57, 5851. (d) CoCl2: Ahmad, S.; Iqbal, J. J. Chem. Soc. Chem. Commun. 1987, 2, 114. (e) DMAP/CCl4: Kamijo, T.; Yamamoto, R.; Harada, H.; Iizuka, K. Chem. Pharm. Bull. 1983, 31, 3724.
    (61) (a) Bi(OTf)3: Mohammadpoor-Baltork, I.; Aliyan, H.; Khosropour, A. R. Tetrahedron 2001, 57, 5851. (b) K5CoW12O40-3H2O: Habibi, M. H.; Tangestaninejad, S.; Mirkhani, V.; Yadollahi, B. Synth.Commun. 2002, 32, 863. (c) Sn (IV) tetraphenylporphyrin perchlorate: Tangestaninejad, S.; Habibi, M. H.; Mirkhani, V.; Moghadam, M. Synth. Commun. 2002, 32; 1337.
    (62) (a) Conversion of aniline to acetanilide was failed in Cp*2 Sm(thf)2 mediated acetylation. (b) Ishii, Y.; Takeno, M.; Kawasaki, Y.; Muromachi, A.; Nishiyama, Y.; Sakaguchi, S. J. Org. Chem. 1996, 61, 3088.
    (63) For the use of group-VIb oxometallic complexes in oxidation processes, see: ref 34a. (b) Ueyama, N.; Kamabuchi, K.; Nakamura, A. J. Chem. Soc. Dalton Trans. 1985, 635. (b) Nakamura, A.; Ueyama, N.; Okamura, T.-A.; Zaima, H.; Yoshinaga, N. J. Mol. Catal. 1989, 55, 276.
    (64) See the Supporting Information for details.
    (65) Pivalations did not work properly due to the poor solubility of these substrates in pivalic anhydride.
    (66) (a) Brownish cellulose acetate was obtained by using conventional procedures before purification. (b) Cellulose acetate with 55% acetate content could be synthesized at 80 oC for 12 hours in catalytic MoO2Cl2.
    (67) Unpublished results from this laboratory.
    (68) (a) Matsumoto, H.; Matsuda, T.; Nakata, S.; Mitoguchi, T.; Kimura, T.; Hayashi, Y.; Kiso, Y. Bioorg. Med. Chem. 2001, 9, 417. (b) Matsumoto, H.; Sohma, Y.; Kimura, T.; Hayashi, Y.; Kiso, Y. Bioorg. Med. Chem. Lett. 2001, 11, 605.
    (69) The documented procedure required the use of benzoyl chloride at -78 oC and Et3N and then gradually warmed to ambient temperature, see: Palomo, C.; Arrieta, A.; Cossio, F. P.; Aizpurua, J. M.; Mielgo, A.; Aurrekoetxea, N. Tetrahedron Lett. 1990, 31, 6429.
    (70) p-nitrobenzoic anhydride has been utilized in macrolactonization of ω-hydroxy-acids catalyzed by Sc(OTf)3, see: ref 23a.
    (71) Sagami; US 4086136; 1978; Chem. Abstr. 1978, 89, 180369w.
    (72) (a) Paredes, R.; Agudelo, F.; Taborda, G. Tetrahedron Lett. 1996, 37, 1965. (b) Vyas, D. M.; Skonezny, P. M.; Jenks, T. A.; Doyle, T. W. Tetrahedron Lett. 1986, 27, 3099.
    (73) (a) Barlos, K.; Kallitsis, J.; Mamos, P.; Patrianakou, S.; Stavropoulos, G. Liebigs Ann. Chem. 1987, 633. (b) Sivvas, E.; Voukelatou, G.; Kouvelas, E. D.; Francis, G. W.; Aksnes, D. W.; Papaioannou, D. Acta Chem. Scand. 1994, 48, 76.
    (74) (a) Anaya, J.; Barton, D. H. R.; Caballero, M. C.; Gero, S. D.; Grande, M. Tetrahedron: Asym. 1994, 5, 2137. (b) Sliskovic, D. R.; Picard, J. A.; Roark, W. H.; Essenburg, A. D.; Krause, B. R. Bioorg. Med. Chem. Lett. 1996, 6, 713.
    (75) Murakami, M.; Hajima, M.; Takami, F.; Yoshioka, M. Heterocycles 1990, 31, 2055.
    (76) Saitoh, K.; Shiina, I.; Mukaiyama, T. Chem.Lett. 1998, 7, 679.
    (77) Kelly, R. C.; Schletter, I.; Stein, S. J.; Wierenga, W. J. Am. Chem. Soc. 1979, 101, 1054.
    (78) By p-TSA/hot benzene or toluene, see: (a) Ichikawa, A.; Hiradate, S.; Sugio, A.; Kuwahara, S.; Watanabe, M.; Harada, N. Tetrahedron Asym. 1999, 10, 4075. (b) Tamiya, J.; Sorensen, E. J. J. Am. Chem. Soc. 2000, 122, 9556. (c) Goodall, K.; Parsons, A. F. Tetrahedron Lett. 1997, 38, 491. (d) Whitesell, J. K.; Nabona, K.; Deyo, D. J. Org. Chem. 1989, 54, 2258. (e) Kupchan, S. M. J. Pharm. Sci. 1965, 54, 514. (f) Loupy, A.; Monteux, D. A. Tetrahedron 2002, 58, 1541. By DCC, see: (g) Tripathy, R.; Carroll, P. J.; Thornton, E. R. J. Am. Chem. Soc. 1991, 113, 7630. (h) Ghosh, A. K.; Chen, Y. Tetrahedron Lett. 1995, 36, 6811. (i) Pelzer, R.; Scharf, H.-D.; Buschmann, H.; Runsink, J. Chem. Ber. 1989, 122, 1187. By carbonyldiimidazole, see: (j) Huebscher, J.; Barner, R. Helv. Chim. Acta. 1990, 73, 1068. By dipyridyl disulfide and Ph3P, see: (k) Akiyama, T.; Nishimoto, H.; Ozaki, S. Tetrahedron Lett. 1991, 32, 1335.
    (79) (a) Iimura, S.; Manabe, K.; Kobayashi, S. Org. Lett. 2002, 5, 101. (b) Sibi, M. P.; Chen, J Org. Lett. 2002, 4, 2933.
    (80) (a) For N-tert-butylamides see 81a. For tert-butylthio esters, see: (b) Mann, A.; Quaranta, L.; Reginato, G.; Taddei, M. Tetrahedron Lett. 1996, 37, 2651. (c) Demarcus, M.; Ganadu, M. L.; Mura, G. M.; Porcheddu, A.; Quaranta, L.; Reginato, G.; Taddei, M. J. Org. Chem. 2001, 66, 697. (d) Gennari, C.; Vulpetti, A.; Donghi, M.; Mongelli, N.; Vanotti, E. Angew. Chem. Int. Ed. Engl. 1996, 108, 1809. (e) Gierasch, T. M.; Shi, Z.; Verdine, G. L Org. Lett. 2003, 5, 621.
    (8 ) For representative examples, see: (a) Kunz, H.; Pfrengle, W. J. Am. Chem. Soc. 1988, 110, 651. (b) Semple, J. E.; Levy, O. E.; Minami, N. K.; Owens, T. D.; Siev, D. Bioorg. Med. Chem. Lett. 2000, 10, 2305. (c) Madsen, U.; Frydenvang, K.; Ebert, B.; Johansen, T. N.; Brehm, L.; Krogsgaard-Larsen, P. J. Med. Chem. 1996, 39, 183. (d) Roxburgh, C. J.; Ganellin, R. C.; Shiner, M. A. R.; Benton, D. C. H.; Dunn, P. M. J. Pharm. Pharmacol. 1996, 48, 851. (e) Easton, C. J.; Hutton, C. A.; Merrett, M. C.; Tiekink, E. R. T. Tetrahedron 1996, 52, 7025. (f) Bon, E.; Bigg, D. C. H.; Bertrand, G. J. Org. Chem. 1994, 59, 1904. (g) Carpenter, A. J.; Chadwick, D. J. J. Org. Chem. 1985, 50, 4362.
    (82) (a) Barrett, A. G. M.; Dhanak, D.; Lebold, S. A.; Russell, M. A. J. Org. Chem. 1991, 56, 1894. (b) Kelly, T. R.; Echavarren, A.; Chandrakumar, N. S.; Koeksal, Y. Tetrahedron Lett. 1984, 25, 2127. (c) Baldwin, J. E.; Farthing, C. N.; Russell, A. T.; Schofield, C. J.; Spivey, A. C. Tetrahedron Lett. 1996, 37, 3761. For direct conversions to 1o amides by TFA, see: (d) Huang, W.; Zhang, P.; Zuckett, J.; Wang, L.; Woolfrey, J.; Song, Y.; Jia, Z. J.; Clizbe, L. A.; Su, T.; Tran, K.; Huang, B. Bioorg. Med. Chem. Lett. 2003, 13, 561. For direct conversions to 1o amides by BF3-Et2O, see: (e) Wilt, J. W.; Niinemae, R. J. Org. Chem. 1979, 44, 2533.
    (83) For deprotective amidations by Hg(II), Ag(I), and Cu(I) species, see: (a) Ley, S. V.; Smith, S. C.; Woodward, P. R. Tetrahedron 1992, 48, 1145. (b) Ley, S. V.; Woodward, P. R. Tetrahedron Lett. 1987, 28, 3019. (c) Schmidt, U.; Steindl, F. Synthesis 1978, 544. (d) Kim, H.-O.; Olsen, R. K.; Choi, O.-S. J. Org. Chem. 1987, 52, 4531. (e) Poncet, J.; Dufour, M.-N.; Pantaloni, A.; Castro, B. J. Org. Chem. 1989, 54, 617. For amidation to primary amides by NH3, see: (f) Otsuka, M.; Narita, M.; Yoshida, M.; Kobayashi, S.; Ohno, M. Chem. Pharm. Bull. 1985, 33, 520. (g) Kittaka, A.; Sugano, Y.; Otsuka, M.; Ohno, M Tetrahedron 1988, 44, 2811.
    (84) For deprotective esterifications by Ag(I) species, see: (a) Lopez-Alvarado, P.; Avendano, C.; Menendez, J. C. Synthesis 1998, 2, 186. (b) Lopez-Alvarado, P.; Avendano, C.; Menendez, J. C. Tetrahedron Lett. 2001, 42, 4479. (c) Sodeoka, M.; Sampe, R.; Kojima, S.; Baba, Y.; Usui, T.; Ueda, K.; Osada, H. J. Med.Chem. 2001, 44, 3216. (d) Clive, D. L. J.; Hisaindee, S. J. Org. Chem. 2000, 65, 4923. By Tl(ONO2)3, see: (e) Mukai, C.; Kim, I. J.; Furu, E.; Hanaoka, M.; Tetrahedron 1993, 49, 8323. (f) Mukai, C.; Kim, I. Jong; Hanaoka, M. Tetrahedron: Asym. 1992, 3, 1007. By Hg(NO3)2, see: (g) Gennari, C.; Vulpetti, A.; Pain, G. Tetrahedron 1997, 53, 5909.
    (85) Bekker, R. A.; Rozov, L. A.; Popkova, V. Y.; Knunyants, I. L. Bull. Acad. Sci. USSR Div. Chem. Sci. (Engl. Transl.) 1982, 31, 2123.
    (86) For peptide synthesis with Fmoc--amino acid anhydrides, see: Fu, Y.; Hammer, P. Org. Lett. 2002, 4, 237.
    (87) For general thio ester preparation, see: Imamoto, T.; Kodera, M.; Yokoyama, M. Synthesis 1982, 2, 134.
    (88) Fedor, L. R. J. Am. Chem. Soc. 1969, 91, 913.
    (89) Nitta, H.; Yu, D.; Kudo, M.; Mori, A.; Inoue, S. J. Am. Chem. Soc. 1992, 114, 7969.
    (90) (a) Neises, B.; Steglich, W. Angew. Chem. Int. Ed. Engl. 1978, 90, 556. (b) Tsuda, M.; Muraoka, Y.; Someno, T.; Nagai, M.; Aoyagi, T.; Takeuchi, T. J. Antibiot. 1996, 49, 900. (c) Ruderisch, A.; Pfeiffer, J.; Schurig, V. Tetrahedron: Asym. 2001, 12, 2025. (d) Horiki, K. Synth. Commun. 1977, 7, 251.
    (9 ) Yokoyama,Y. Chem. Pharm. Bull. 1977, 25, 2423.
    (92) Bernardi, A.; Piarulli, U.; Poli, G.; Scolastico, C.; Villa, R. Bull. Soc. Chim. Fr. 1990, 6, 751.
    (93) (a) Benzotriazolyl-N-oxytris(dimethylamino)phosphonium salts: Dormoy; C. Tetrahedron Lett. 1979, 3321. For representative examples, see: (b) Spivey, A. C.; Capretta, A.; Frampton, C. S.; Leeper, F. J.; Battersby, A. R. J. Chem. Soc. Perkin Trans.1 1996, 17, 2091. (c) Sliedregt, K. M.; Schouten, A.; Kroon, J.; Liskamp, R. M. J. Tetrahedron Lett. 1996, 37, 4237. (d) Frerot, E.; Coste, J.; Pantaloni, A.; Dufour, M.-N.; Jouin, P Tetrahedron 1991, 47, 259. (e) Schiller, P. W.; Weltrowska, G.; Nguyen, T. M.-D.; Wilkes, B. C.; Chung, N. N.; Lemieux, C. J. Med. Chem. 1993, 36, 3182. (f) Perree-Fauvet, M.; Verchere-Beaur, C.; Tarnaud, E.; Anneneim-Herbelin, G.; Bone, N.; Gaudemer, A. Tetrahedron 1996, 52, 13569. (g) McGeary, R. P. Tetrahedron Lett. 1998, 39, 3319. (h) Albericio, F.; Bofill, J. M.; El-Faham, A.; Kates, S. A. J. Org. Chem. 1998, 63, 9678. (i) Fray, M. J.; Burslem, M. F.; Dickinson, R. P. Bioorg. Med. Chem. Lett. 2001, 11, 567.
    (94) (a) Rychnovsky, S. D.; Hu, Y.; Ellsworth, B. Tetrahedron Lett. 1998, 39, 7271. (b) Reddy, M. V. R.; Brown, H. C.; Ramachandran, P. V. J. Organomet. Chem. 2001, 624, 239. (c) Rychnovsky, S. D.; Marumoto, S.; Jaber, J. J. Org. Lett. 2001, 3, 3815.
    (95) (a) Baldwin, J. E.; Schofield, C. J.; Smith, B. D Tetrahedron 1990, 46, 3019. (b) Baldwin, J. E.; Bradley, M.; Adlington, R. M.; Norris, W. J.; Turner, N. J. Tetrahedron 1991, 47, 457. (c) Jensen, S. E.; Westlake, D. W. S.; Bowers, R. J.; Ingold, C. F.; Jouany, M. Can. J. Chem. 1984, 62, 2712. (d) Baldwin, J. E.; Lynch, G. P.; Schofield, C. J. Tetrahedron 1992, 48, 9085. (e) Karpavichyus, K. I.; Prasmitskene, G. I.; Palaima, A. I.; Knunyants, I. L. Bull. Acad. Sci. USSR Div. Chem. Sci. (Engl.Transl.) 1981, 30, 144. (f) Baldwin, J. E.; Adlington, R. M.; Crouch, N. P.; Mellor, L. C.; Morgan, N. Tetrahedron 1995, 51, 4089. (g) Harding, R. L.; Henshaw, J.; Tilling, J.; Bugg, T. D. H. J. Chem. Soc. Perkin Trans.1 2002, 14, 1714.
    (96) For Rink amide-type resins, see: Rink, H. Tetrahedron Lett. 1987, 28, 4645
    (97) (a) Nishizuka, T.; Hirosawa, S.; Kondo, S.; Ikeda, D.; Takeuchi, T. J. Antibiot. 1997, 50, 755. (b) Patel, S.; Saroglou, L.; Floyd, C. D.; Miller, A.; Whittaker, M. Tetrahedron Lett. 1998, 39, 8333. (c) Takashiro, E.; Nakamura, Y.; Miyamoto, S.; Ozawa, Y.; Sigiyama, A.; Fujimoto, K. Bioorg. Med. Chem. 1999, 7, 2105. (d) Perola, E.; Xu, D.; Kollmeyer, T. M.; Kaufmann, S. H.; Prendergast, F. G.; Pang, Y.-P. J. Med. Chem. 2000, 43, 401. (e) Salvadori, S.; Guerrini, R.; Balboni, G.; Bianchi, C.; Bryant, S. D.; Cooper, P. S.; Lazarus, L. H. J. Med. Chem. 1999, 42, 5010.
    (98) (a) Rasmusson, G. H.; Reynolds, G. F.; Steinberg, N. G.; Walton, E.; Patel, G. F. J. Med. Chem. 1986, 29, 2298. (b) Bhattacharya, A.; Williams, J. M.; Amato, J. S.; Dolling, U.-H.; Grabowski, E. J. J. Synth. Commun. 1990, 20, 2683. (c) Bhattacharya, A.; DiMichele, L. M.; Dolling, D.-H.; Douglas, A. W.; Grabowski, E. J. J. J. Am. Chem. Soc. 1988, 110, 3318. (d) Cabeza, M.; Heuze, I.; Bratoeff, E.; Murillo, E.; Ramirez, E.; Lira, A. Chem. Pharm. Bull. 2001, 49, 1081. (e) Frye, S. V.; Haffner, C. D.; Maloney, P. R.; Mook, R. A.; Dorsey, G. F. J. Med. Chem. 1993, 36, 4313.
    (99) (a) Basak, A.; Rudra, K. R.; Bag, S. S.; Basak, A. J. Chem. Soc. Perkin Trans. 1 2002, 15, 1805. (b) Scholz, D.; Billich, A.; Charpiot, B.; Ettmayer, P.; Lehr, P. J. Med. Chem. 1994, 37, 3079 (c) Benatalah, Z.; Trigui, N.; Sicsic, S.; Tonnaire, T.; de Rosny, E. Eur. J. Med. Chem. Chim. Ther. 1995, 30, 891. (d) Floyd, C. D.; Harnett, L. A.; Miller, A.; Patel, S.; Saroglou, L.; Whittaker, M. Synlett 1998, 6, 637. (e) Fray, M. J.; Burslem, M. F.; Dickinson, R. P. Bioorg. Med. Chem. Lett. 2001, 11, 567. (f) Threadgill, M. D.; Gledhill, A. P. J. Org. Chem. 1989, 54, 2940.
    ( 00) (a) Kamenar, B.; Korpar-Čolig, B.; Penavić, M. J. Chem. Soc. Dalton Trans. 1981, 311. (b) Kamenar, B.; Penavić, M.; Korpar-Čolig, B.; Marković, B. Inorg. Cryst. Struct. Comm. 1981, 10, 961.
    (10 ) An in-situ formation of MoO2(OR)2 was excluded by simple mixing of MoO2Cl2 and ROH without intermediacy of a base, see: (a) Nebelung, V. A.; Jahr, K. F. Z. Naturforsch. 1964, 19B, 654. (b) Topich, J. Inorg. Chim Acta 1980, 46, L37. (c) Topich, J. Inorg. Chem. 1981, 20, 3704. (d) McCabe D. J.; Duesler, E. N.; Paine, R. T. Inorg. Chem. 1987, 26, 2300. (e) Kim, G.-S.; Huffman, D.; Dekock, C. W. Inorg. Chem. 1989, 28, 1279.
    ( 02) Pivalic anhydride was used instead of trifluoroacetic anhydride at the current study due to the ease of monitoring the catalytic process with reasonably time span.
    ( 03) Less than 50% conversion was observed when acetic anhydride and 2-phenylethanol were premixed before addition of MoO2Cl2 in CD2Cl2.
    ( 04) A significantly slower rate (by a factor of 8) was observed with sequential addition of 2-phenylethanol and pivalic anhydride.
    (105) Disulfide bond cleavage has been known in NAS catalyzed by PBu3 or Sc(OTf)3, see: ref-12b.
    (106) Grubbs, R. H. Comprehensive Organometallic Chemistry; Wilkinson, G..; Stone, F. G. A.; Abel, E. W. Eds.; Pergamon Press: New York, 1982, Vol. 8, Chapt. 54, 499.
    ( 07) (a) Casella, L.; Gullotti, M.; Pintar, A. Inorg. Chim. Acta 1988, 144, 89. (b) Clarke, R.; Gahagan, M.; Mackie, R. K.; Foster, D. F.; Cole-Hamilton, D. J.; Nicol, M.; Montford, A. W. J. Chem. Soc. Dalton Trans. 1995, 1221. (c) Kamiyama, T.; Inoue, M.; Enomoto, S. Chem. Lett. 1989, 1129. (d) For an unexpected deprotection of TBS ethers by MoO2(acac)2 and TBHP, see: Hanamoto, T.; Hayama, T.; Katsuki, T.; Yamaguchi, M. Tetrahedron Lett. 1987, 6329. For a review on oxymetal-mediated epoxidation, see: Lane, B. S.; Burgess, K. Chem. Rev. 2003, 103, 2457.
    ( 08) (a) Colonna, S.; Manfredi, A.; Spadoni, M.; Casella, L.; Gullotti, M. J. Chem. Soc. Perkin Trans. 1 1987, 71. For oxidation of organic substrates, see: (b) Klemperer, W. G.; Mainz, V. V. Wang, R.-C.; Shum, W. Inorg. Chem. 1985, 24, 1968. (c) Nitteberg, E. B.; Rokstad, O. A. Acta Chem. Scand. A 1980, 34, 199.
    ( 09) (a) Mo(O)2Cl2 is compatible with water at ambient temperature and can be converted to MoO3 in boiling water, see: Neikirk, D. L.; Fagerli, J. C.; Smith, M. L.; Mosman, D.; Devore, T. C. J. Mol. Struct. 1991, 244, 165. (b) For an elegant survey of water tolerant metal salts, see: Kobayashi, S.; Nagayama, S.; Busujima, T. J. Am. Chem. Soc. 1998, 120, 8287.
    ( 10) All the applications in Scheme 2 could also be achieved with equal efficacy by using VO(OTf)2 as the catalyst.
    (111) Otera, J. Chem. Rev. 1993, 93, 1449.
    (112) Rehberg, C. E.; Fisher, C. H. J. Am. Chem. Soc. 1944, 66, 1203.
    (113) Rehberg, C. E.; Faucette, W. A.; Fisher, C. H. J. Am. Chem. Soc. 1944, 66, 1723.
    (114) Rehberg, C. E. Organic Synthesis. 1955, 3, 146.
    (115) Hagenmeyer, H. J. Jr.; Hull, D. C. Ind. Eng. Chem. 1949, 41, 2920.
    (116) Rothman, E. S.; Hecht, S. S.; Pfeffer, P. E.; Silbert, L. S. J. Org. Chem. 1972, 37, 3551.
    (117) DeWolfe, R. H. Synthesis 1974, 153.
    (118) Reimer, M.; Downes, H. R. J. Am. Chem. Soc. 1921, 43, 945.
    (119) Taft, R. W., Jr.; Newman, M. S.; Verhoek, F. H. J. Am. Chem. Soc. 1950, 72, 4511.
    (120) Billman, J. H.; Smith, W. T.,Jr.; Rendall, J. L. J. Am. Chem. Soc. 1947, 69, 2058.
    (121) Frank, R. L.; Davis, H. R., Jr.; Drake, S. S.; McPherson, J. B., Jr. J. Am. Chem. Soc. 1944, 66, 1509.
    (122) Rossi, R. A.; de Rossi, R. H. J. Org. Chem. 1974, 39, 855.
    (123) Pereira,W.; Close, V.; Patton, W.; Halpern, B. J. Org. Chem. 1969, 34, 2032.
    (124) Taber, D. F.; Amedio, J. C. Jr.; Patel, Y. K. J. Org. Chem. 1985, 50, 3618.
    (125) Motter, C.; Hamelin, O.; Depres. J.-P. J. Org. Chem. 1999, 64, 1380.
    (126) Seebach, D.; Thaler, A.; Blaser, D.; Ko. S. Y. Helv. Chim. Acta 1991, 74, 1102.
    (127) (a)Kunz, H.; Waldmann, H. Angew. Chem. Int. Ed. Engl. 1983, 22, 62. (b) Waldmann, H.; Kunz, H. J. Org. Chem. 1988, 53, 4172.
    (128) Kubota, M.; Yamamoto, T.; Yamamoto, A. Bull. Chem. Soc. Jpn. 1979, 52, 146.
    (129) Kim, Y.-J.; Osakada, K.; Takenaka, A.; Yamamoto, A. J. Am. Chem. Soc. 1990, 112, 1096.
    (130) Blossey, E. C.; Turner, L. M.; Neckers, D. C. Tetrahedron Lett. 1973, 1823.
    (131) (a)Yazawa, H.; Tanaka, K.; Kariyone, K. Tetrahedron Lett. 1974, 3995. (b) Yamamoto, H.; Ishihara, K.; Ohara, S. Science 2000, 1140.
    (132) Pereyre, M.; Colin, G.; Delvigne, J.-P. Bull. Soc. Chim. Fr. 1969, 262.
    (133) (a) Otera, J.; Yano, T.; Kawabata, A.; Nozaki, H. Tetrahedron Lett. 1986, 27, 2383. (b) Otera, J.; Dan-oh, N.; Nozaki, H. J. Org. Chem. 1991, 56, 5307.
    (134) (a) Otera, J.; Ioka, S.; Nozaki, H. J. Org. Chem. 1989, 54, 4013-4014.(b) Giannis, A.; Baumhof, P.; Mazitschek, R. Angew. Chem. Int. Ed. 2001, 40. 3672.
    (135) (a) Seebach, D.; Hungerbuhler, E.; Naef, R.; Schnurrenberger, D.; Weidmann, B.; Zuger, M. Synthesis, 1982, 138. (b) Seebach, Scheffold, R., Ed.; Otto Salle: Frankfurt, 1983; Vol. 3, p 217. (c) Imwinkelreid, R.; Schiess, M.; Seebach, D. Org. Syn. 1987, 65, 230.
    (136) Mukayyama, T.; Inubushi, A.; Suda, S.; Hara, R.and Kobayashi, S. Chem. Lett. 1990, 1015.
    (137) Bortolini, O.; Furia, F. D. and Modena, G. J. Mole. Cat, 1985, 33, 241.
    (138) Hwang, D. R.; Chen, C. P. and Uang, B. J. J. Chem. Soc. Chem. Commun. 1999, 1207.
    (139) Stephen, D.; Hessell, E. T. J. Organomet. Chem. 1987, 263.
    (140) Advanced Organic Chemistry (Fourth Edition), Carey Sundberg pp.822.
    (141) Bertrand, G. J. Org. Chem. 1994, 59, 4035.
    (142) Ponde, D. E.; Deshpande, V. H.; Bulbule, V. J.; Sudalai, A.; Gajare, A. S. J. Org. Chem. 1998, 63, 1058.

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