Mukaiyama aldol addition to alpha-chloro-substituted aldehydes. Origin of the unexpected syn selectivity.
The addition of sterically demanding enolsilanes to alpha-chloro aldehydes results unexpectedly in preferential formation of the anti-PFA product (1,2-syn), while the addition of the corresponding boron enolate furnishes the expected polar Felkin-Anh product (1,2-anti). A stereoinduction model explaining these observations is proposed.
Borg
Tessie
T
Organic Chemistry, KTH Chemical Science and Engineering, Royal Institute of Technology, 100 44 Stockholm, Sweden.
Danielsson
Jakob
J
Somfai
Peter
P