Regiochemistry and Stereochemistry of Nickel-Promoted, Carbon-Carbon Bond-Forming Reactions of Cyclic Sulfur Compounds

Article abstract of DOI:10.1021/jo00220a029

Reaction of methylmagnesium iodide and phenylmagnesium bromide with thianaphthene, dibenzothiophenone, thianthrene, and 2,3-dihydrothiapyran in the presence of <1,3-bis(diphenylphosphino)propyl>nickel dichloride have been shown to yield, regioselectively in most cases, ring-opened products in which the carbon-sulfur bonds have been replaced by carbon-carbon bonds.Stereospecific carbon-carbon bond formation has taken place in the reactions of thianaphthene and 2,3-dihydrothiapyran, the products having maintained the cis-olefin configuration of the starting sulfur compounds.Isomerization into the more stable compounds has been observed in some cases.