Diastereoselective Henry reaction catalyzed by guanidine-thiourea bifunctional organocatalyst

作者：Sohtome Y; Takemura N; Iguchi T; Hashimoto Y; Nagasawa K^*

来源：Synlett, 2006, (1): 144-146.

DOI：10.1055/s-2005-922770

• bifunctional organocatalyst
• guanidine
• thiourea
• Henry reaction
• diastereoselective reaction

A highly diastereoselective Henry reaction (diastereomer ratio of 84:16 to 99:1) of a-substituted aldehydes with nitromethane was developed using guanidine-thiourea bifunctional catalyst 1. N,N-Dibenzyl-protected alpha-amino aldehydes (2a, 2d-h) and alpha-hydroxy aldehydes protected as silyl ethers (2i-j) were suitable substrates. The matched combination of this catalytic system, i.e., S-aldehydes and (R,R)-1 catalyst, can be understood in terms of the transition state of the asymmetric version of the Henry reaction catalyzed by 1.

• 出版日期2006-1-5