Carbonylation of methanol at unusually low temperature and pressure with cis-RhCl(CO)2Ph2P(CH2)2P(O)Ph2

cis-RhCl(CO)2Ph2P(CH2)2P(O) Ph2, the only species observed during catalysis, formed from cis-[graphic omitted])Ph2 and CO, is the sole active species observed during catalytic studies and results in the carbonylation of methanol with catalyst turnover frequencies approaching 400 h–1 at 80 °C and 50 psig CO; the crystal structure of the analogue cis-[graphic omitted])Ph2 is reported.