One-pot asymmetric synthesis of tert-butanesulfinyl-protected amines from ketones by the in situ reduction of tert-butanesulfinyl ketimines

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• 作者：Borg ; George ; Cogan ; Derek A. ; Ellman ; Jonathan A.
• 刊名：Tetrahedron Letters
• 出版年：1999
• 出版时间：September 10, 1999
• 年：1999
• 卷：40
• 期：37
• 页码：6709-6712
• 全文大小：226 K

文摘

A one-pot method for the asymmetric synthesis of tert-butanesulfinyl-protected amines is described. The ketones 2 are condensed with (R)-tert-butanesulfinamide 1 and the tert-butanesulfinyl imine intermediates reduced in situ with NaBH₄ to afford the sulfinamides 4 in 66-86 % yield and with drs from 90:10 to 97:3 for both aryl alkyl and dialkyl ketones. Ti(OEt)₄ serves as both a water scavenger and catalyst for imine condensation, and as a Lewis acid that provides enhanced reduction rates and dr.