Interception of a Rh(I)–Rh(III) dinuclear trihydride complex revealing the dihydrogen activation by [Rh(CO)2{(R,R)-Ph–BPE}]

Reaction of [Rh(CO)2{(R,R)-Ph–BPE}][BF4] 1 under 7 bar H2 provides the dihydride [Rh(H)2(CO)2{(R,R)-Ph–BPE}][BF4] 3, which reacts with the neutral hydride [Rh(H)(CO){(R,R)-Ph–BPE}] 2 arising from 3 in THF. The resulting complex is the dimeric monocationic Rh(I)–Rh(III) complex [Rh(H)2(CO)2{(R,R)-Ph–BPE}][BF4] 4.