CRYSTAL AND MOLECULAR-STRUCTURE OF ALLYLNITROSYLBIS(TRIPHENYLPHOSPHINE)RUTHENIUM, RU(NO) (ETA-3 C3H5)(P(C6H5)3)2

The reaction of RuCl(NO) (PPh3)2 with tetraallyltin produces the mixed allyl-nitrosyl complex Ru(NO) (η3-C3H5) (PPh3)2, whose structure has been determined from three-dimensional X-ray data collected by counter techniques. The material crystallizes in the space group P2, of the monoclinic system with two molecules in the unit cell. Crystal data are a = 9.04 (1)Å, b = 17.47 (3) Å, c= 11.51 (2) Å,β= 115.39 (8)°, ρmeasd = 1.409 (5) g/cm3, and ρcalcd = 1.410 g/cm3. The structure has been refined by a full-matrix least-squares procedure to conventional discrepancy factors R1 and R2 of 0.0299 and 0.0383 for 2190 observations having Fo2 > 3ρ(Fo2). The coordination geometry about the ruthenium atom is best described as distorted tetrahedral, similar to other four-coordinate 18-electron complexes. Both the allyl and nitrosyl ligands act as three-electron donors. Important distances and angles are Ru-Cl = 2.214 (7) Å, Ru-C2 = 2.130 (7) Å, Ru-C3 = 2.258 (8) Å, Ru-N =1.751 (6) Å, C1-C2-C3 = 117.7 (7)°, and Ru-N-O = 173.8 (6)°. A comparison of this structure with those of the isoelectronic complexes Ru(NO)2(PPh3)2 and Ru(η3-C3H5)2(PPh3)2 is made, and the η3 mode of allyl coordination is discussed. © 1978, American Chemical Society. All rights reserved.