Hydrophosphination of unactivated alkenes, dienes and alkynes: A versatile and valuable approach for the synthesis of phosphines

The last years have seen many advances in the field of organometallic catalysis. Motivating much of the work has been the potential for discovering new catalytic reactions, which can be used for the synthesis, of bulky chemicals and fine chemical intermediates. Since the efficiency and the selectivity of the catalyst mainly rely on the. structure of the ligand, there is a great interest in the design and the synthesis of new ligands (amines, amino-alcohols, thioether, phosphines etc). From all of them, phosphine derivatives are the most widely used with transition metal catalysts. Different approaches have allowed to prepare phosphine derivatives: nucleophilic. substitution of a P-chloro derivative, nucleophilic substitution using metal phosphide, C-P cross coupling etc. A greener way to phosphines is the addition of a P-H bond to a multiple bond since no atom loss is observed (atom economy concept). These reactions are mainly carried out in the presence of radical initiators or under basic conditions. Acidic and neutral media were also proposed. A few-recent examples reported the,use-of a metal activation. This review is designed to remember some of the early aspects of hydrophosphination reactions using phosphines, protected or not, and unactivated or slightly activated alkenes, dienes and alkynes and to focus on the more promising results obtained in this field for the last 15 years. The reactions involving pentavalent phosphorus derivatives (phosphine-oxide, thiophosphines, phosphonate and phosphate derivatives etc.) are not concerned by this chapter.