Kristall- und Molekülstruktur von Tetrakis(4-fluorophenylisonitril)rhodium(I)chloridhydrat und Tetrakis(4-nitrophenylisonitril)rhodium(I)chlorid / Crystal and Molecular Structure of Tetrakis(4-fiuorophenylisonitrile)rhodium(I) Chloride Hydrate and Tetrakis(4-nitrophenylisonitrile)rhodium(I) Chloride

Abstract

4-Fluorophenylisonitrile and 4-nitrophenylisonitrile react with μ-dichloro-bis[dicarbo-nylrhodium(I)] [Rh(CO₂)Cl]₂ yielding the blue tetrakis(4-fluorophenylisonitrile)rhodium-(I)chloride hydrate (1) and the dark green tetrakis(4-nitrophenylisonitrile)rhodium(I) chloride (2). Yellow Perchlorates 3 (of 1) and 4 (of 2) can be obtained from both compounds. 1 crystallizes in the monoclinic space group P 2₁/c with a - 10.57(2) Å, b = 11.459(5) Å, c = 23.71(5) Å, β = 107.14(4)°, Z = 4. Compound 2 crystallizes in the triclinic space group P1̄ with a = 12.34(4) Å, b = 10.704(3) Å, c = 13.703(3) Å, α = 106.58(2)°, β = 106.07(4)°, γ = 108.29(3)°, Z = 2. 3 belongs to the rhombic space group Pnmm or Pnm2 with a = 11.523(4) Å, b= 15.48(1) Å, c= 15.915(9) Å, Z = 4 and 4 is triclinic with a = 6.987(4) Å, b = 14.300(7) Å, c == 16.983(7)1, α = 71.89(3)°, β = 89.20(4)°, γ = 79.54(4)°, Z = 2. The structures of 1 and 2 were determined by Patterson and Fourier methods from diffractometer data and refined by least squares to R - 0.062 (1) or R = 0.157 (2). Crystals of both compounds contain metal-to-metal bonded dimers with a Rh-Rh bond distance of 3.207(2) Å in 1 and 3.25(1) Å in 2. the ligands of the two adjacent complex units taking an eclipsed position. These dimers are arranged in layers. There is a second type of layer in 1 containing the water molecules which are hydrogen bonded to the chloride counterions. The blue color of 1 is caused by a strong absorption at 16700 cm^-1 (597 nm). 2 has a similar absorption band at 16500 cm^-1 (606 nm). Compounds 3 and 4 contain the monomeric complex units.