The generation and cyclization of several heterocyclic radicals were investigated. The hydrogen abstraction from 1, 3-dithiane, 1, 3-dithiolane, and 1, 3-oxathiane rings by a benzophenone triplet generated the corresponding heterocyclic radicals, which gave the cyclized products by intramolecular addition to α, β-unsaturated esters. Diastereoselective radical cyclization using chiral acetals was also investigated.
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