The efficient synthesis of chiral or achiral tertiary phosphines bearing an o-bromo (or iodo) aryl substituent is described. The key step of this synthesis is based on the reaction of a secondary phosphine borane with the 1, 2-dibromo (or diiodo) arene, owing to the formation in situ of an aryne species in the presence of n-butyllithium. When P-chirogenic secondary phosphine boranes were used, the corresponding o-halogeno-arylphosphine boranes ...
