Phosphonation of aryl halides under photostimulation

Following the (apparently) initial observations by Griffin and coworkers on the irradiation of mixtures of aryl iodides and trialkyl phosphites, it was evident that the procedure held great promise for synthesis although it was found necessary to employ 3-5 molar excess of phosphite ester (to allow for competitive photostimulated Michaelis-Arbuzov isomerization to dialkyl alkylphosphonate), nevertheless yields were very high, sometimes 

A detailed study of the mechanism and scope of the process has been carried out over a period of several years by Bunnett and coworkers Using 350 nm radiation, it has been found that while the reaction between Arl and metal dialkyl phosphite takes place during 45-200 min in liquid other solvents, including dmso, MeCN and dmf are also high- 

Savignac and coworkers drew a comparison between the transition metal-catalysed and the photostimulated phosphonation reactions and concluded that the latter process produced more uniformly good results, and also showed that the addition of one equivalent Nal to mixtures of aryl bromide and metal dialkyl phosphite greatly accelerated the phosphonation process .  

Oxidative phosphonylation of aromatic compounds with phosphorus(lll) esters 

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