General One-Pot Reductive<i>gem</i>-Bis-Alkylation of Tertiary Lactams/Amides: Rapid Construction of 1-Azaspirocycles and Formal Total Synthesis of (±)-Cephalotaxine
the first generalmethod for the direct transformation of tertiary lactams/amides into tert‐alkylamines. The method is based on in situ activation of amide with triflic anhydride/2,6‐di‐tert‐butyl‐4‐methylpyridine (DTBMP), followed by successive addition of two organometallic reagents of the same or different kinds to form two CC bonds. Both alkyl and functionalized organometallic reagents and enolates
A practical method for the synthesis of gem-2,2-disubstituted tertiary amines from the corresponding lactams (or amides) is reported. It is based on the reaction of thioiminium ions, easily prepared from lactams and amides with organometallic reagents such allylmagnesium, benzylmagnesium, and primary alkylcerium reagents.