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33.4.19.1.1.7.1 Variation 1: Cyclization Involving a Halogen Leaving Group

DOI: 10.1055/sos-SD-033-00680

Quirion, J.-C.Science of Synthesis, (200733641.

A series of articles describe the preparation of optically pure alcohols 51, which have then been used to prepare the 1,2,3,4-tetrahydropyridines 52 (Scheme 24).[‌27‌‌30‌] Many conditions have been explored for performing the key cyclization step; the best results are obtained using halogenation conditions (CBr4/Ph3P or I2/Ph3P/1H-imidazole) then cyclization with or without isolation of the intermediate halide.

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References