Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6.
J Am Chem Soc. 2009 Nov 18;131(45):16404-6. doi: 10.1021/ja9072194.
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.
两性氨基醛作为稳定的二聚体参与氮杂迈克尔/羟醛缩合的串联反应,与α,β-不饱和醛反应,以高产率和高非对映选择性得到稳定的 1,5-氨基羟醛。反应结果取决于两性氨基醛的二聚体性质以及反应过程中 NH 氮杂环丙烷和两个醛官能团之间的正交性。通过使用不利于二聚体解离的反应条件,氮杂迈克尔过程被导向新颖的 8-(烯醇内型)-endo-外消旋环化。本文所描述的结果进一步证明了两性分子在反应发现中的潜力。