Phenylthio cyclooctanone

A stirred suspension of the adduct (1) (0.668 g, 1.2 mmol) in dichloromethane (10ml) was treated with l-(trimethylsilyloxy)cyclooctene (0.198g, l.Ommol). After completion of the reaction (—20 min) the solution was concentrated in vacuo and the residue was partitioned between ether (50 ml) and water (15 ml). The organic phase was dried (MgS04) and concentrated in vacuo. The resulting solids were applied to a short column of silica gel (hexanes/ethyl acetate 7 3) to give 2-(phenylthio)cyclooctanone (0.20g, 92%) as an oil. 

The oxidation step can be avoided if sulfinylation of the carbonyl compound can be conveniently realized. Methyl 2-pyridinesulfinate (2) has been prepared and used for sulfinylation-dehydrosulfinylation of ketones (Table 3.1) and esters [216]. 

Dehydrogenation of ketones with methyl 2-pyridinesulfinate Ketone Product Yield (%) 

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Phenyl 4-pentenedithioate 42 2-(Phenylthio)cyclooctanone 55 Phenylthiomethyllithium 86 Pummer reaction 64,81... 

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