112794-25-9Relevant academic research and scientific papers
Polynuclear acetylides. Synthesis, spectroscopic features, and structural systematics for a complete triad of μ2-η2-Complexes: M2(CO)6(μ2-η 2-C≡CR)(μ-PPh2) (M = Fe, Ru, Os)
Cherkas, Andrew A.,Randall, Leslie H.,MacLaughlin, Shane A.,Mott, Graham N.,Taylor, Nicholas J.,Carty, Arthur J.
, p. 969 - 977 (2008/10/08)
The synthesis of the triad of phosphido-bridged, acetylide-bridged dimetallic carbonyls M2(CO)6(μ2-η2-C 2R)(μ-PPh2) (1, M = Fe; 2, M = Ru; 3, M = Os; a, R = Ph, b, R = t-Bu, c, R = i-Pr) is described. The molecules 1, 2, and 3 were prepared via pyrolysis of M3(CO)11(Ph2PC≡CR) which initiates metal metal bond cleavage and oxidative addition of the P-C(acetylide) bond across a metal-metal edge. Compounds 1b, 2b, and 3b have been structurally characterized by single-crystal X-ray analysis. Crystals of 1-3b are monoclinic of space group P21/n with unit cell dimensions. 1b: a = 15.140 (3) A?, b = 10.559 (2) A?, c = 16.659 (3) A?, β = 110.61 (1)°. 2b: a = 12.549 (1) A?, b = 14.528 (2) A?, c = 14.266 (1) A?, β = 92.95 (1)°. 3b: a = 15.357 (2) A?, b = 10.604 (2) A?, c = 16.969 (2) A?, β = 111.56 (1)°. The structures were solved and refined to the following R and Rw values: 1b, R = 0.028, Rw = 0.031 on 3071 observed (I ≥ 3σ(I)) data; 2b, R = 0.028, Rw = 0.030 on 4349 observed (I ≥ 3σ(I)) data; 3b, R = 0.035, Rw = 0.040 on 2734 observed (I ≥ 3σ(I)) data. The three molecules are isostructural with a metal-metal bond supported by a phosphido bridge and a σ-π bound acetylide ligand. In solution all three compounds are fluxional via processes of acetylide σ-π interchange and M(CO)3 trigonal rotation. Changes in structural parameters down the triad are discussed.
