Bimetallic catalysis: synthesis of benzophenones through carbonylation of aryl iodides catalysed by Fe(CO)5-Co2(CO)8 systems.

Article abstract of DOI:10.1016/0022-328X(90)87066-M

The direct, catalytic carbonylation of aryl iodides to give the corresponding benzophenones is reported for the first time.Under phase transfer conditions (aq.NaOH/C6H6/Bu4NBr) and under 1 atm pressure of carbon monoxide, iron pentacarbonyl alone promotes the conversion of iodobenzene to benzophenone and benzoic acid whereas dicobaltoctacarbonyl alone promotes a slow carbonylation to give solely benzoic acid.A synergetic effect is observed when the reaction is carried out in the presence of catalytic amounts of both carbonyl metals, and benzophenone can be isolated in more than 50percent yield.Under these conditions, o-iodotoluene affords the corresponding 2,2'-dimethylbenzophenone in 47percent isolated yield.