chapter  3
48 Pages

Photocycloadditions with Captodative Alkenes

An alkene 1. hearing both an electron donor d and an electron acceptor c at one terminus of the double bond, may he termed a captodativc alkene. Addition of a radical R to its double bond will occur strictly rcgioselcctivcly at the unsub-

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stituted terminus and generate a captodatively (c,d)-stabilized adduct radical 2 [I] (Scheme 1).