Zirconium-Catalyzed Reaction of 1-Alkynyl Sulfides with Et₃Al: A Novel Route to Trisubstituted 1-Alkenyl Sulfides

Abstract

The reaction of 1-alkynyl sulfides and alkynyl sulfoxides with Et₃Al under zirconocene catalysis conditions has been studied. The interaction between 1-alkynyl sulfides and Et₃Al in the presence of catalytic amounts of Cp₂ZrCl₂ leads to trisubstituted 1-alkenyl sulfides in moderate to good yields (56–73%) with high regioselectivity and stereo­selectivity. 1-Alkynyl sulfoxides, upon treatment with Et₃Al under the same reaction conditions, undergoes reduction to give sulfides. The excess of Et₃Al (7 equiv) in this reaction causes cyclic carboalumination of in situ generated 1-alkynyl sulfide to form trisubstituted 1-alkenyl sulfides in quantitative yield.

Key words

1-alkynyl sulfides - 1-alkynyl sulfoxides - zirconocene catalysis - 1-alkenyl sulfides - cyclic carboalumination

• References and Notes

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