A chiral ligand-mediated asymmetric addition of a lithium BHA ester enolate to an aldehyde.
The asymmetric reaction of a lithium enolate generated from a BHA (2, 6-di-tert-buty-4-methoxyphenyl) propanoate was allowed to react with benzaldehyde in the presence of a diether-type chiral ligand affording the corresponding anti-aldol product in a moderate enantioselectivity. A tetradentate ligand induced better enantioselectivity albeit relative loss of anti-selectivity. A variation of lithiating amide agent affected the selectivity, indicating involvement of an amine as a component of the mixed aggregate. Absolute configuration of some of the aldol products was determined by standard transformations.
Version: za2963e q8zaf q8zb9 q8zc9 q8zd0 q8ze1 q8zf1 q8zg1