Abstract
The first catalytic enantioselective Reformatsky reaction is realized by a controlled
transmetalation of an α-iodo ester with dimethylzinc in the presence of a chloromanganese-Salen
complex (20 mol%) as catalyst and 4-phenylpyridine N -oxide (25 mol%) as additive. The zinc enolate is formed under mild conditions at
room temperature; it undergoes enantioselective addition to ketones. The reaction
shows broad scope and moderate to good stereoselection and it allows the straightforward
preparation of quaternary stereogenic centers.
Key words
Reformatsky reaction - enantioselective - catalysis - chloromanganese-Salen complex
- dimethylzinc
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