Remote asymmetric induction by the vinylogous Mukaiyama aldol reaction using the acetate-type vinylketene silyl N,O-acetal possessing a chiral auxiliary has been achieved. The silyl N,O-acetal derived from crotonate and l-valine afforded the O-silylated 5R- and 5S-adducts selectively by treatment with SnCl and BF·OEt, respectively. The SnCl-mediated isomerization of silyl dienol ether was found, and the resulting major isomer showed high reactivity to give γ-adduct in high stereoselectivity.
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