Asymmetric hydrogenation of vinylphosphonic acids carrying a phenyl substituent at

2 ASYMMETRIC HYDROGENATION OF VINYLPHOSPHONIC ACIDS CARRYING A PHENYL SUBSTITUENT AT C2 

All reactions were carried out in solution under argon. 

A solution of the appropriate substrate (lmmol or 6 mmol) in degassed methanol (2 mL to 5 mL) was added to the Ru(II) catalyst. 

The glass vessel was placed under argon in a stainless steel autoclave, which was then pressurized with hydrogen. 

The enantiomeric excesses of the phosphonic acids were measured using 31 P NMR after treatment with (IS, 2S)-(—)-N,A -dimethyl(diphenylethy-lene)-diamine in CDC13 and a catalytic amount of CD3OD. 

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