Thioesters allylic, formation

Subsequently, the same authors synthesized allyl multifunctionalized (Z)-keto allyl halides 241 via the HX4 or TiX4/Bu4NI-mediated vicinal difunctionalization of a,p-unsaturated ketones (at room temperature) " and thioesters (reflux) " with aldehydes in good to excellent yields and complete (Z/ ) stereoselectivity (Scheme 2.141). The formation of halo aldol adducts 242 and 242 was also observed in the case of vinyl ketones when the reaction was conducted at 0°C (Scheme 2.141). ... 

Trost and coworkers extended their protocol to 2-acylimidazoles after accomplished enantioselective decarboxylative allylation of this type of ketones, the heterocycle was cleaved under formation of y,8-unsaturated esters. Thus, this protocol can be considered an equivalent of the enantioselective allylic alkylation of carboxylic esters [55a]. For the same purpose, the decarboxylative allylation of Af-acyloxazolinones was developed. The allylation products were converted, under cleavage of the heterocycle, into carboxylic acids, esters, and thioesters in high enantiomeric purity [55b]. 

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