Crystal structure of chloro[1,2,3,4-(tetramethoxycarbonyl)buta-1,3-dien- 1,4-diyl]-bis(triphenylphosphine)iridium(III), [Ir{C4(COOCH3)4}Cl{P(C6H5)3}2]

C48H42ClIrO8P2, orthorhombic, P212121 (No. 19), a = 21.146(3) Å, b = 11.198(2) Å, c = 18.200(4) Å, V = 4309.6 Å, Z = 4, Rgt(F) = 0.021, wRref(F) = 0.040, T = 220 K. Source of material The reaction of [IrCl(N2)(PPh3)2] with (MeOOC)2C C(COOMe)2 in acetone at 283 K resulted in the formation of the title complex [Ir{C4(COOMe)4}Cl(PPh3)2] which was previously obtained in the analogous reaction in thiophene-free benzene at 313 K – 318 K [1,2]. Crystals were obtained from methanol/chloroform solution. Experimental details Two carbon atoms C8 and C8A of the ester group on C2 are disordered over two positions with equal occupancies (0.50). For clarity only one position is shown in the figure. The hydrogen atoms of that methyl group were not localized and not included into the model. All other hydrogen atoms are placed in calculated positions according to the riding model. Discussion There are several examples of structurally characterized iridacyclopentadiene complexes [3,4]. However, five-fold coordination in mononuclear complexes is found only in one single case [5]. Here we report the second example of that type. The title compound crystallizes as discrete molecules without any unusual intermolecular interactions. The trigonal bipyramidal co-ordination sphere of Ir is built up by two PPh3 ligands in apical positions. The angle P1–Ir–P2 is almost linear with 177.64(3)°. Equatorial ligands are the chloro ligand and the -bound buta-1,3-dien-1,4-diyl ligand. The sum of angles in the equatorial plane ( C1–Ir–C4 = 76.4(2)°, C1–Ir–Cl = 146.8(1)°, C4–Ir–Cl = 136.8(1)°) amounts to 360.0°. The Ir—C1 and Ir—C4 bond distances are 2.015(4) Å and 2.011(4) Å, respectively. Overall, there are no remarkable differences in the bond lengths and angles of the title complex compared with those in other iridacyclopentadiene complexes. Z. Kristallogr. NCS 218 (2003) 115–117 115 © by Oldenbourg Wissenschaftsverlag, München Crystal: red block, size 0.12 × 0.13 × 0.15 mm Wavelength: Mo K radiation (0.71073 Å) : 32.89 cm Diffractometer, scan mode: Stoe IPDS, 2 max: 49.98° N(hkl)measured, N(hkl)unique: 31004, 7588 Criterion for Iobs, N(hkl)gt: Iobs > 2 (Iobs), 6604 N(param)refined: 551 Programs: SHELXS-97 [6], SHELXL-97 [7], ORTEP-III [8] Table 1. Data collection and handling. H(3) 4a 0.7338 1.1813 0.4224 0.104 H(2) 4a 0.6746 1.1950 0.3713 0.104 H(1) 4a 0.7391 1.2534 0.3488 0.104 H(4) 4a 0.8569 0.7391 0.0154 0.103 H(6) 4a 0.8097 0.6314 0.0098 0.103 H(5) 4a 0.8746 0.6156 0.0504 0.103 H(9) 4a 0.8229 0.3430 0.2147 0.112 H(8) 4a 0.8656 0.3835 0.1489 0.112 H(7) 4a 0.7922 0.4022 0.1453 0.112 H(14) 4a 0.9247 0.6003 0.5510 0.036 H(15) 4a 0.9237 0.6162 0.6793 0.043 H(16) 4a 0.8507 0.7415 0.7353 0.053 H(17) 4a 0.7819 0.8531 0.6664 0.042 H(18) 4a 0.7806 0.8339 0.5399 0.037 H(20) 4a 0.9805 0.6080 0.4151 0.047 H(21) 4a 1.0239 0.4240 0.3891 0.057 Table 2. Atomic coordinates and displacement parameters (in Å). Atom Site x y z Uiso