Abstract
Enolsilanes and silyl ketene acetals add to aryl aldimines complexed with tricarbonylchromium, often at ambient temperature, with very high diastereoselectivity in the presence of 5 mol% Sc(OTf)3 to afford β-amino ketones and β-amino esters in excellent yield. The β-amino esters were cyclized to β-lactams by treatment with MeMgI.
Key words
arene-chromium - scandium triflate - imino aldol reaction - diastereoselective
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