Menthyl phenylglyoxalate

Optically active a-hydroxy carboxylic acids. The organozinc reagents prepared in situ from RMgX and ZnCl2 or ZnBr2 add selectively to the keto group of - l-menthyl phenylglyoxalate (1). The adducts are hydrolyzed to optically active a-hydroxy carboxylic acids (3).1... 

Figure 6.9. Temperature dependence of the diastereoselectivity of oxetane formation (22 , 23 A, 24 ) by cycloaddition of menthyl phenylglyoxalate (19) to tetra-methylethylene (20) and ketene acetal (21) (by permission from Biischmann et al., 1991).

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