Mechanistic and synthetic aspects of amine oxidations promoted by 3-methyl-5-ethyllumiflavinium perchlorate
摘要:
Preparative and kinetic aspects of the chemistry of 3-methyl-5-ethyllumiflavinium perchlorate (1) with primary and secondary amines have been investigated. Reactions of 1 with primary and secondary amines leads to rapid production of modestly stable C4a-adducts. The rates of these processes, determined by stopped-flow kinetic methods, parallel amine nucleophilicities. The C4a-adducts undergo benzylamine promoted elimination reactions to produce N-benzylaldimine products with fates that parallel reactivity profiles expected for E(2)-elimination processes. Finally, flavinium salt 1 serves as a catalyst for oxidations of primary and secondary amines under aerobic conditions. (C) 1997 Elsevier Science Ltd.
描述了旨在探测黄素促进的胺氧化脱氨基的研究。已发现 3-甲基发光黄素 (3MLF) 在酸(HCl 或 MgCl 2 )催化的热(80 o C)条件下促进苄胺向 N-苄基苯扎二亚胺的清洁转化。该反应受多重周转的影响。发现胺结构 (1 o >2 o >3 o ) 和 α-电离基团离开能力 (TMS + >H + ) 会影响反应性。此外,发现使用 PhCHDNH 2 为基态反应测量的内部 d-同位素效应为 4.3,该值与在几乎相同(20 o C 而不是 80 o C) 条件