Amphoteric Amino Aldehydes Reroute the Aza-Michael Reaction
作者:Ryan Hili、Andrei K. Yudin
DOI:10.1021/ja9072194
日期:2009.11.18
Amphoteric amino aldehydes, which exist as stable dimers, participate in an aza-Michael/aldol domino reaction with alpha,beta-unsaturated aldehydes to afford stable 1,5-aminohydroxyaldehydes in high yields and diastereoselectivies. The reaction outcome hinges upon the dimeric nature of amphoteric amino aldehydes and the orthogonality between the NH aziridine and the two aldehyde functionalities during the reaction. Through the use of reaction conditions that disfavor dimer dissociation, the aza-Michael process has been directed toward a novel 8-(enolendo)-exo-trig cyclization. The results described herein further demonstrate the potential of amphoteric molecules in reaction discovery.
A Versatile Synthetic Platform Based on Strained Propargyl Amines
作者:Zhi He、Andrei K. Yudin
DOI:10.1002/anie.200906066
日期:2010.2.22
Divergent reactivity: Various ethynylaziridines behave as strained propargyl amines and can be directly converted into unprotected α‐amino allenes by a highly diastereoselective SN2′ hydride delivery (see scheme). Additional reaction routes involve chemo‐ and regioselective transformation into either bicyclic aziridine/enol ethers or highly strained azirine alkynes.
不同的反应性:各种乙炔基氮丙啶表现为应变的炔丙基胺,可通过高度非对映选择性的S N 2'氢化物传输直接转化为未保护的α-氨基丙二烯(参见方案)。其他反应途径包括化学和区域选择性转化为双环氮丙啶/烯醇醚或高度紧张的叠氮炔。