Synthesis of Optically Active Permethric Acid

The straightforward synthesis of optically active single isomers of permethric acid is accomplished, when the diazoacetic acid synthesis is carried out in the presence of 

Another less surprising route to the 1-R-ds-add is given by the intramolecular carbene addition of the optically active diazoacetic ester 200 [345, 342] (Reaction scheme 129). The optical yield here is determined by the optical purity of the 

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