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Metalloporphyrin-Mediated Asymmetric Nitrogen-Atom Transfer to Hydrocarbons: Aziridination of Alkenes and Amidation of Saturated C−H Bonds Catalyzed by Chiral Ruthenium and Manganese Porphyrins

2002; Wiley; Volume: 8; Issue: 7 Linguagem: Inglês

10.1002/1521-3765(20020402)8

1521-3765

Jiang‐Lin Liang, Jie‐Sheng Huang, Xiao‐Qi Yu, Nianyong Zhu, Chi‐Ming Che,

Asymmetric Hydrogenation and Catalysis

Chemistry – A European JournalVolume 8, Issue 7 p. 1563-1572 Full Paper Metalloporphyrin-Mediated Asymmetric Nitrogen-Atom Transfer to Hydrocarbons: Aziridination of Alkenes and Amidation of Saturated C−H Bonds Catalyzed by Chiral Ruthenium and Manganese Porphyrins Jiang-Lin Liang, Jiang-Lin Liang Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this authorJie-Sheng Huang Dr., Jie-Sheng Huang Dr. Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this authorXiao-Qi Yu Dr., Xiao-Qi Yu Dr. Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this authorNianyong Zhu Dr., Nianyong Zhu Dr. Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this authorChi-Ming Che Prof., Chi-Ming Che Prof. [email protected] Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this author Jiang-Lin Liang, Jiang-Lin Liang Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this authorJie-Sheng Huang Dr., Jie-Sheng Huang Dr. Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this authorXiao-Qi Yu Dr., Xiao-Qi Yu Dr. Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this authorNianyong Zhu Dr., Nianyong Zhu Dr. Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this authorChi-Ming Che Prof., Chi-Ming Che Prof. [email protected] Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong (China) Fax: (+852) 2857-1586Search for more papers by this author First published: 28 March 2002 https://doi.org/10.1002/1521-3765(20020402)8:7 3.0.CO;2-VCitations: 202Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Graphical Abstract Good to excellent aziridine or amide selectivities have been observed from mass balance studies for the enantioselective aziridination or enantio/diastereoselective amidation of hydrocarbons (including cholesteryl acetate) with PhI=NTs or “PhI(OAc)2 + NH2R (R=Ts, Ns, or SO2Me)” catalyzed by chiral metalloporphyrin 1 or 2 (see scheme). The “PhI(OAc)2 + NH2SO2Me” amidation of benzylic hydrocarbons catalyzed by 1 or 2 realized an enantioselective formation of N-substituted methanesulfonamides from metal-catalyzed direct amidation of saturated C−H bonds. Abstract Chiral metalloporphyrins [Mn(Por*)(OH)(MeOH)] (1) and [Ru(Por*)(CO)(EtOH)] (2) catalyze asymmetric aziridination of aromatic alkenes and asymmetric amidation of benzylic hydrocarbons to give moderate enantiomeric excesses. The mass balance in these nitrogen-atom-transfer processes has been examined. With PhI=NTs as the nitrogen source, the aziridination of styrenes, trans-stilbene, 2-vinylnaphthalene, indene, and 2,2-dimethylchromene catalyzed by complex 1 or 2 resulted in up to 99 % substrate conversions and up to 94 % aziridine selectivities, whereas the amidation of ethylbenzenes, indan, tetralin, 1-, and 2-ethylnaphthalene catalyzed by complex 2 led to substrate conversions of up to 32 % and amide selectivities of up to 91 %. Complex 1 or 2 can also catalyze the asymmetric amidation of 4-methoxyethylbenzene, tetralin, and 2-ethylnaphthalene with “PhI(OAc)2 + NH2SO2Me”, affording the N-substituted methanesulfonamides in up to 56 % ee with substrate conversions of up to 34 % and amide selectivities of up to 92 %. Extension of the “complex 1 + PhI=NTs” or “complex 1 + PhI(OAc)2 + NH2R (R=Ts, Ns)” amidation protocol to a steroid resulted in diastereoselective amidation of cholesteryl acetate at the allylic C−H bonds at C-7 with substrate conversions of up to 49 % and amide selectivities of up to 90 % (α:β ratio: up to 4.2:1). An aziridination- and amidation-active chiral bis(tosylimido)ruthenium(VI) porphyrin, [Ru(Por*)(NTs)2] (3), and a ruthenium porphyrin aziridine adduct, [Ru(Por*)(CO)(TsAz)] (4, TsAz=N-tosyl-2- (4-chlorophenyl)aziridine), have been isolated from the reaction of 2 with PhI=NTs and N-tosyl-2-(4-chlorophenyl)aziridine, respectively. The imidoruthenium porphyrin 3 could be an active species in the aziridination or amidation catalyzed by complex 2 described above. The second-order rate constants for the reactions of 3 with styrenes, 2-vinylnaphthalene, indene, ethylbenzenes, and 2-ethylnaphthalene range from 3.7–42.5×10−3 dm3 mol−1 s−1. 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