Photo-induced 1,2-carbohalofunctionalization of C-C multiple bonds via ATRA pathway
Debojyoti Bag1, Harpreet Kour1, Sanghapal D Sawant1
1Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Jammu, Canal Road, Jammu, Jammu & Kashmir 180001, India. sdsawant@iiim.res.in.
Abstract:
Radical vicinal carbohalofunctionalization of C-C multiple bonds via atom transfer processes constitutes an efficient method for the construction of halogenated building blocks with complete atom economy via radical cleavage of a pre-existing carbon-halogen σ-bond of an atom transfer reagent and their transposition over the π-bond of alkenes and alkynes. This review summarizes the recent advances in the photo-induced version of this class of transformations. A variety of transition-metal complexes, organic dyes, phosphines, amines, phenols and aldehydes were utilized as catalysts for the cleavage of the existing carbon-halogen bond of the corresponding atom transfer reagent in the presence of a light source. Alongside a variety of 1,2-haloalkylation and haloperfluoroalkylation reactions, atom transfer radical addition (ATRA) or cyclization (ATRC) reactions via the cleavage of the carbon-halogen bonds of aryl halides are also discussed.
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