Enantioselective Phosphorus and Arsenic Ylide Catalysis

Barbas et al. found that replacing the N-Boc group with a benzyl or amide protecting group could significantly improve the enantioselectivity, while at a lower 

In Lu s work, the hydrogen-bonding interactions between the thiourea moiety of the bifunctional catalyst 37 and the indolinone 33b were proposed to account 

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