Pentakis(methoxycarbonyl)cyclopentadiene chemistry XII. Some rhodium and iridium derivatives: X-ray crystal structures of Rh(η4-C8H12)5-C5(CO2Me)5>, Rh(azb)2, and (PPh3)2> (M = Rh and Ir)

Article abstract of DOI:10.1016/0022-328X(89)87008-1

The reaction between 4-C8H12)> and Tl gave Rh(η⁴-C8H12)<η⁵-C5(CO2Me)5> (3), which with PPh2(CH2)2PPh2 (dppe) gave 4-C8H12)>.The complex Rh(azb)2 (6; azb = C6H4N2Ph) was obtained from 2 and Tl.Crystallographic characterisation of 3 and 6 showed that in the former, the C5(CO2Me)5 group is attached via the ring carbons, whereas in 6, the ligand chelates the metal via two ester CO groups.Reactions of Tl with MCl(CO)(PPh3)2 in MeCN gave (7, M = Rh; 8 M = Ir), in which the MeCN ligand is converted into (probably) acetic acid during recrystallisation, as shown by structural studies of the isomorphous Rh and Ir salts, 11 and 12.The ^- anion is hydrogen-bonded to this acetic acid ligand.Crystal data: 3, triclinic, space group P1<*>, a 18.591(3), b 14.053(4), c 10.395(3) Angstroem, α 75.15(2) β 72.13(2), γ 81.38(2) deg, Z = 4; 6, monoclinic, space group P2₁/n a 23.897(5), b 9.900(1), c 15.828(3) Angstroem, β 99.56(2) deg, Z = 4; 11, triclinic, space group P1<*>, a 21.695(7), b 13.669(7), c 9.319(3) Angstroem, α 103.15(3), β 95.39(3), γ 98.20(3) deg, Z = 2; 12, triclinic, space group P1<*>, α 21.685(2), b 13.615(2), c 9.306(2) Angstroem, α 103.34(2), β 95.28(2), γ 98.31(1) deg, Z = 2.For the four structure determinations 6343, 5024, 3785 and 5462 observed data with I>/= 3?(I) were refined to R 0.043 (3), 0.042 (6), 0.064 (11) and 0.057 (12), respectively