The catalyst Rh(Ph 2 PCH 2 CH 2 PPh 2 ) can be prepared by the reaction of Rh(nbd)(Ph 2 PCH 2 CH 2 PPh 2 ) (nbd 25 37) with two equivalents of H 2 In coordinating solvents Rh(Ph 2 PCH 2 CH 2 PPh 2 ) , in the form of a solvated complex Rh(Ph 2 PCH 2 CH 2 PPh 2 )(solv) 2 , catalyses the hydrogenation...

A The reaction of RhnbdPh2PCH2CH2PPh2 with H2 typically involves oxidative addition of H2 to the met ...

The catalyst [Rh(Ph 2 PCH 2 CH 2 PPh 2 )] + can be prepared by the

Question:

The catalyst [Rh(Ph₂PCH₂CH₂PPh₂)]⁺ can be prepared by the reaction of [Rh(nbd)(Ph₂PCH₂CH₂PPh₂)]⁺ (nbd = 25.37) with two equivalents of H₂. In coordinating solvents [Rh(Ph₂PCH₂CH₂PPh₂)]⁺, in the form of a solvated complex [Rh(Ph₂PCH₂CH₂PPh₂)(solv)₂]⁺, catalyses the hydrogenation of RCH=CH₂.

(a) Draw the structure of [Rh(nbd)(Ph₂PCH₂CH₂PPh₂)]⁺ and suggest what happens when this complex reacts with H₂.

(b) Draw the structure of [Rh(Ph₂PCH₂CH₂PPh₂)(solv)₂]⁺, paying attention to the expected coordination environment of the Rh atom.

(c) Given that the first step in the mechanism is the substitution of one solvent molecule for the alkene, draw a catalytic cycle that accounts for the conversion of RCH=CH₂ to RCH₂CH₃. Include a structure for each intermediate complex and give the electron count at the Rh centre in each complex.