79391-63-2Relevant academic research and scientific papers
[o-phenylenebis(dimethylarsine)]heptacarbonyldiiron. Preparation, crystal structure, and fluxionality in solution
Bailey, Webb I.,Bino, Avi,Cotton, F. Albert,Kolthammer, Brian W. S.,Lahuerta, Pascual,Puebla,Uson
, p. 289 - 294 (1982)
The reaction of Fe2(CO)9 with o-phenylenebis(dimethylarsine), diars, in an atmosphere of CO gives yellow (diars)Fe2(CO)8 and red (diars)Fe2(CO)7, separable by chromatography on silica. The red compound crystallizes in space group P1 with Z = 2 and the following unit cell dimensions: a = 9.706 (4) ?; b = 11.876 (3) ?; c = 9.576 (3) ?; α = 92.41 (2)°; β = 104.81 (2)°; γ = 91.25 (2)°; V= 1066 (1) ?3. The structure consists of dinuclear molecules in which diars is chelated on one iron atom (Fe(1)) to which are also bound two terminal CO groups. Fe(1) also forms a metal-metal bond, 2.566 (1) ?, to Fe(2), which bears three strictly terminal CO groups. Of the remaining two CO groups, one forms a nearly symmetrical bridge while the other is semibridging with its short bond, 1.894 (7) ?, to Fe(2) and its long bond, 2.103 (7) ?, to Fe(1). The 13C NMR spectrum is highly temperature dependent, changing from a five-line spectrum (1:2:2:1:1) at -132°C to a single-line spectrum at 11°C. A three-stage process for equivalencing all of the CO's is proposed.
