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Updated: Jan 22, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Dimeric Potassium Amide-Catalyzed α-Alkylation of Benzyl Sulfides and 1,3-Dithianes
Abstract:
The first catalytic α-alkylation reaction of benzyl sulfides and 1,3-dithianes with styrenes and conjugated dienes was developed under mild conditions by using a readily available Brønsted base potassium bis(trimethylsilyl)amide (KHMDS) as catalyst. The reaction displayed good functional group tolerance, high efficiency, and excellent chemoselectivity. A series of desired alkylation products were obtained in good to high yield. Preliminary mechanism studies suggested that two of the potassium amide catalyst molecules worked together in the catalytic cycle.
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