Synthesis of rhodium and iridium boryl complexes via oxidative addition of haloboranes

B-Chlorocatecholborane oxidatively adds to M(PR3)3Cl (M = Rh, R = Me; M = Ir, R = Me, Et) yielding six-coordinate mer,cis- (PR3)3Cl2M(BO2C6H4) complexes whereas reaction with B-bromocatecholborane gives a mixture of homo- and heterodihalides (PR3)3X1X2M(BO2C6H4) (X1, X2 = Cl, Br), the disproportionation probably involving formation of a heteronuclear halide bridged intermediate.