c ~s -R ~C I ( C O ) ~P ~~P ( C H ~) ~P ( O ) P ~~, the only species observed during catalysis, formed from cis-hhCI(CO)Ph2P(CH2P(~)Ph2 and CO, is the sole active species observed during catalytic studies and results in the carbonylation of methanol with catal st turnover frequencies approaching 400 h-1 at 80°C and 50 psig CO; the crystal structure of the analogue cis-hCI(CO)Ph2PCH2P(0)Ph2 is reported.

No abstract

Metal-ion exchanged heteropoly acids of the general formula M[W12P040] (M = a group Vlll metal) supported on S O 2 have been found to be excellent catalysts for the vapour phase carbonylation of methanol or dimethyl ether to methyl acetate at 225°C and 1 atm total operating pressure.

No abstract

Organometallics 1982, 1, 47-52 47 group protons is only 0.04 ppm downfield from that of 1 (with R = CH3) reported previ~usly.~ In addition, only the signals of the bipyridyl protons are observed.The structure as determined by X-ray analysis ( Figure 1) is in accord with the IR and NMR spectroscopic evidence but reveals additional details, most notably an extremely distorted octahedral coordination geometry around the molybdenum atom, which is in part even more pronounced than that in 3.l Although complexes 3 and 4 crystallize in the same space group (Pi), the 0-Mo-0 angle of 110.20O is 7' wider than in 4; the C-Mo-C angle of 149.03' is loo smaller than the Br-Mo-Br angle. These differences in the bond angles are caused by repulsions of the methyl groups by the two cis-oxygen atoms. Because of the negative inductive effect of the methyl groups, the charge density on the oxygen atoms in 4 is probably higher than in 3. However, the average Mo-O bond distances of 1.71 A in 4 are within experimental error identical with those in 3. Table VI shows that the average Mo-C bond (7) R.