Mannich reaction of carbonyl compounds via boron enolates and N,N,N′,N′-tetramethyldiaminomethane
作者:Ernest G. Nolen、Andrea Allocco、Jim Vitarius、Karen McSorley
DOI:10.1039/c39900001532
日期:——
A variety of carbonylcompounds undergo N,N-dimethylaminomethylation in moderate to good yields by the Mannichreaction involving boronenolates and N,N,N′,N′-tetramethyldiaminomethane in dichloromethane.
Reversal of aldehyde diastereofacial selectivity in a methyl ketone aldol reaction. Application to the synthesis of the calyculin spiroketal
作者:David A. Evans、James R. Gage
DOI:10.1016/s0040-4039(00)97005-9
日期:1990.1
It has been observed that aldehyde diastereofacialselectivity in a methyl ketone aldol reaction can be fully regulated under appropriate conditions. Addition of the lithium enolate provided the product derived from apparent chelation control, while Lewis acid-promoted addition of the derived silyl enolether afforded the Felkin-Anh diastereomer. Application of this methodology to the ongoing synthesis