A Convenient and Useful Method of Preparation of α-Bromo Enones from the Corresponding Enones Using Organic Ammonium Tribromide (OATB)
Various acyclic α-bromo enones 2 as well as cyclic α-bromo enones 4 can be prepared from the corresponding acyclic enones 1 and cyclic enones 3 respectively, in a one-pot procedure by employing organic ammonium tribromide, such as cetyltrimethylammonium tribromide (CetTMATB) or tetrabutylammonium tribromide (TBATB) in presence of K2CO3 in dichloromethane at 0 °C to room temperature under very mild conditions in good yields.2