Abstract t-Butyldimethylsilyl acetaldehyde (3) is obtained from the hydrolysis of the (Z)-β- silylenoxysilane (2), prepared from (Z-1-bromo-2-(trimethylsiloxy) ethylene by reaction with t- butyllithium followed by condensation with t-butyldimethylsilyl triflate. The lithium enolate of aldehyde 3 is prepared direct by reaction with lithium diisopropylamide or lithium hexamethyldisilazane; its condensation with trimethylchlorosilane leads to the (E)-β- ...