General synthesis of alkyl phenyl selenides from organic halides mediated by zinc in aqueous medium

Organic halides of different structural types react with diphenyl diselenid e and zinc dust in aqueous medium to give alkyl phenyl selenides. Benzylic and allylic bromides, alpha -bromoesters, acids and ketones and some primar y alkyl iodides produce high yields even under acidic conditions. Less reac tive halides need basic medium. The reaction proceeds equally well in the p resence of various unprotected functional groups. Control experiments suppo rt a S(H)2 mechanism via alkyl radicals. (C) 2001 Elsevier Science Ltd. All rights reserved.