ON THE USE OF beta PHENYLSULFINYL- alpha , beta -UNSATURATED CARBONYL DIENEOPHILES IN DIELS-ALDER REACTIONS.

Article abstract of DOI:10.1021/ja00517a038

The use of beta -phenylsulfinyl- alpha , beta -unsaturted carbonyl dieneophiles as synthetic equivalents of alpha , beta -ethynyl carbonyl systems has been demonstrated. The sulfoxides were prepared by oxidation of the sulfides, which in turn were obtained from the beta -dicarbonyl systems by standard methods. A key feature of the scheme is that the phenylsulfinyl group does not compete with the carbonyl function in determining the regiochemistry of cycloaddition with the highly nucleophilic trans-1-methoxy-3-trimethylsilyloxy-1,3-butadiene. Application of the methodology to the synthesis of the disodium prephenate dimethyl acetals is described.