Organocatalytic Asymmetric Bromination of Alkenes

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The preparation of chemicals as single enantiomers is of vital importance in the fields of pharmaceutical chemistry, fine chemicals and academia. The use of a chiral catalyst in order to do so is widely recognised as the most efficient way of inducing asymmetry. Several excellent methods exist for catalytic asymmetric synthesis of eg epoxides, and these act as building blocks for the preparation of other enantiopure materials.To date the catalytic asymmetric bromination of alkenes has not been achieved. This is somewhat surprising given that bromination is a classic textbook reaction, and the potential utility of the obtained enantiomerically pure bromides by stereospecific nucleophilic displacement with a wide-range of nucleophiles.We propose herein to develop a general catalytic asymmetric bromination reaction of alkenes. The catalysts will be based on 2,6-disubstituted iodobenzenes where the de facto catalytic entity will have a hypervalent X-I-Br bond. The catalysts will be designed so that the electrophilic bromine is a region of high asymmetry.