In hydrofomylation reaction using $\mathrm{[Rh(PPh_3)_2(CO)(H)]}$ as the catalyst, addition of excess $\mathrm{PPh_3}$, would
(a)increase the rate of reaction
(b)decrease the rate of reaction.
(c)not influence of the rate of reaction
(d)stop the reaction.
Answer
Answer: B ✓ checked by 4AB · confidence high
Explanation
PPh₃ must dissociate from [RhH(CO)(PPh₃)₂] to open a site for the alkene; excess PPh₃ suppresses this and lowers the rate (while improving linear selectivity) (b).