Reactions of aminobenzoic acids with α,β-acetylenic γ-hydroxy nitriles: synthesis of functionalized amino acids and unusually facile esterification and acetylene hydration
作者:Boris A. Trofimov、Anastasiya G. Mal'kina、Olesya A. Shemyakina、Valentina V. Nosyreva、Angela P. Borisova、Alexander I. Albanov、Olga N. Kazheva、Grigorii G. Alexandrov、Anatolii N. Chekhlov、Oleg A. Dyachenko
DOI:10.1016/j.tet.2009.01.073
日期:2009.3
1 reacts with α,β-acetylenic γ-hydroxy nitriles 4 and 5 to afford 2-[(5-iminio-2,2-dialkyl-2,5-dihydro-3-furanyl)amino]benzenecarboxylates 7 and 8 (yield 73–74%), a new class of unnatural amino acids in a peculiar zwitterionic form, having the positive charge transferred to the remote imino group of the dihydrofuranyl substituent. 3- and 4-Aminobenzoic acids 2 and 3 with α,β-acetylenic γ-hydroxy nitriles
2-氨基苯甲酸1与α,β-炔属γ-羟基腈4和5反应,得到2-[(5-亚氨基-2-2,2-二烷基-2,5-二氢-3-呋喃基)氨基]苯甲酸7和8(收率73-74%)是一类新型的两性离子形式的非天然氨基酸,其正电荷转移到二氢呋喃基取代基的远端亚氨基上。3-和4-氨基苯甲酸2和3与α,β-γ炔羟基腈4 - 6进行完全不同的变换提供cyanomethylhydroxyalkyl酮的酯9 - 12,这是由于羟基官能团的酯化反应异常容易,同时三键同时水合造成的。发现4-氨基苯甲酸3是一种将α,β-炔属γ-羟基腈4一锅转化为5-氨基-2,2-二甲基-3(2 H)-呋喃酮13的活性有机催化剂,收率为80%。