2- phenyl-2-cyclohexenyl acetate

The hydrolytic DKR of allyl esters has been studied as a DKR of esters. The first DKR was accomplished through Pd-catalyzed racemization and enzymatic hydrolysis of allylic acetates in a buffer solution. However, the DKR under these conditions was limited to cyclohexenyl acetates to give symmetrical palladium-allyl intermediates. Among them, 2-phenyl-2-cyclohexenyl acetate 9 was the only substrate to have been resolved with good results (81% yield, 96% ee). 

Scheme 4.60 Palladium-catalysed DKR of 2-phenyl-2-cyclohexenyl acetate.

Cyclohexyne intermediates 709 have been observed as the result of 3-elimination in the reactions of 1-cyclohexenyl(phenyl)iodonium salts 708 with mild bases, such as tetrabutylammonium acetate, fluoride ion,... 

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