Infrared Spectra and Structures of Metal Carbonyl Derivatives. III. Acetylene and Olefin Derivatives of Group VI Metal Carbonyls

A new synthetic route to pentacarbonylalkene complexes of tungsten(0): X-ray crystal structure of [W(CO)5(η2-C2H4)]

“…Thus, saturation of an orange n-heptane solution of [(l-GeCl 2 ){W(CO) 5 } 2 ] compound with ethene leads to precipitation of light yellow amorphous solid of [(lGeCl 2 ) 2 {W(CO) 5 } 2 ] and to the formation of a pale yellow solution of [W(CO) 5 (g 2 -C 2 H 4 )] (1). The identity of 1 has been confirmed by its characteristic IR spectrum [8][9][10] and by X-ray analysis. The pale yellow crystals of 1, suitable for X-ray diffraction studies, were grown during sublimation process carried out in vacuum at room temperature [18].…”

“…As the result, the olefin ligand can be then easily transformed in catalytic reaction. All group 6 metal carbonyls have been shown to undergo reactions with olefin either by thermal substitution of ligands such as tetrahydrofuran, acetone, or acetonitrile [5] or, recently more frequently, by photochemical substitution of carbonyl ligands in hexacarbonyls [4,6-8].Olefin-carbonyl complexes of the type [M(CO) 5 (g 2 -olefin)] and trans-[M(CO) 4 (g 2 -olefin) 2 ] have been known since 1963, when Stolz et al [9] observed the substitution of CO ligands by alkene ligands by IR spectroscopy during UV photolysis of n-hexane solution of hexacarbonyls M(CO) 6 (M = Mo, W) and alkene such as ethene, propene, butene and butadiene. Over the years, a number of group 6 metal carbonyl complexes containing olefin ligands have been reported, including ethene-carbonyl complexes of tungsten, having from one to three g 2 -ethene ligands [6,8,10].…”

“…Olefin-carbonyl complexes of the type [M(CO) 5 (g 2 -olefin)] and trans-[M(CO) 4 (g 2 -olefin) 2 ] have been known since 1963, when Stolz et al [9] observed the substitution of CO ligands by alkene ligands by IR spectroscopy during UV photolysis of n-hexane solution of hexacarbonyls M(CO) 6 (M = Mo, W) and alkene such as ethene, propene, butene and butadiene. Over the years, a number of group 6 metal carbonyl complexes containing olefin ligands have been reported, including ethene-carbonyl complexes of tungsten, having from one to three g 2 -ethene ligands [6,8,10].…”

“…Photolysis of an alkane solution of M(CO) 6 (M = Cr, M, W) and olefin leads first to the formation of a thermally labile [M(CO) 5 (g 2 -olefin)] complex and after further irradiation to a much more stable trans-[M(CO) 4 (g 2 -olefin) 2 ] complex [4,[6][7][8][9][10]. Even prolonged irradiation of M(CO) 6 in the presence of olefin gives a mixture of penta-and tetra-carbonyl compounds.…”

Carbonyltungsten(0) complexes of acryloylferrocene: Synthesis and characterization

“…Olefin-substituted Group 6 metal carbonyls are conveniently accessible from the parent M(CO) 6 complexes (M = Cr, Mo, W) by means of photolytic CO displacement in the presence of olefins: ethene and linear alkenes [15][16][17][18][19], cycloalkenes [19][20][21], a,b-unsaturated esters [22] and tetracyanoethene [23]. A recent kinetic study [24] on the photochemical conversion of W(CO) 6 into a trans-W(CO) 4 (g 2 -olefin) 2 complex using E-cyclooctene as a model olefin owing to its extraordinary coordination properties [25] showed that the photolysis of M(CO) 6 in the presence of an olefin is expected to yield the stable final product trans-M(CO) 4 (g 2 -olefin) 2 through the intermediate M(CO) 5 (g 2 -olefin) and cis-M(CO) 4 (g 2 -olefin) 2 complexes.…”