New Types of Silyl Enolate

TMS enolates and other unstrained triorganosilyl enolates have been widely used 

PhjBOH (0-1 equiv) SDS (0.1 equiv) OSiMe PhCO2H (0.01 equiv) 

The HMPA-catalyzed reaction of homochiral (Z)-enolate 39 generated from the 

CaCl2-catalyzed aldol reaction of DMS enolates proceeds efficiently even in the presence of water. Thus, the catalytic system can be utilized for hydroxymethylation using a commercial aqueous solution of formaldehyde. 

The chemoselective aldol reaction of a-enals with KSA has been achieved under 

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