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A new bis(pyrazol-1-yl)methane ligand,[Ph_2(HO)CCH(3,5-Me_2Pz)_2,Pz=pyrazole] (1),with a bulky substituent on the methine carbon atom has been successfully synthesized by the reaction of bis(3,5- dimethylpyrazol-1-yl)methyllithium with benzophenone. Treatment of this ligand with W(CO)_6 under UV-irradiation in THF at room temperature afforded a novel dinuclear complex CH_2[3,5-Me_2PzW(CO)_5]_2(2) with loss of the Ph_2CO fragment,which was characterized by IR, 1H NMR spectra and elemental analyses as well as the X-ray single crystal diffraction analysis. This compound crystallizes in the orthorhombic space group Pbcn ,with a =1.7690(3) nm,b =1.4460(3) nm, c =1.2994(2) nm,Z =4,V =3.3239(10) nm 3,D _c=1.775 g·cm -3 ,μ =6.967 mm -1 ,F(000)=1672,R _1=0.0414 and wR _2=0.0988. Bis(3,5-dimethylpyrazol-1-yl)methane acts as a bridging bidentate ligand in this complex,which links two W(CO)_5 fragments. In addition,heating this complex under reflux in 1,2-dimethoxyethane (DME) gives the known chelated mononuclear complex CH_2(3,5-Me_2Pz)_2- W(CO)_4(3).
A new bis (pyrazol-1-yl) methane ligand, [Ph_2 (HO) CCH (3,5-Me_2Pz) _2, Pz = pyrazole] (1), with a bulky substituent on the methine carbon atom has been synthesized synthesized by the reaction of bis (3,5- dimethylpyrazol-1-yl) methyllithium with benzophenone. Treatment of this ligand with W (CO) _6 under UV-irradiation in THF at room temperature afforded a novel dinuclear complex CH_2 [3,5-Me_2PzW (CO) _5] _2 (2) with loss of the Ph_2CO fragment, which was characterized by IR, 1H NMR spectra and elemental analyzes as well as the X-ray single crystal diffraction analysis. This compound crystallizes in the orthorhombic space group Pbcn, with a = 1.7690 (3) nm, b = 1.4460 (3) nm, c = 1.2994 (2) nm, Z = 4, V = 3.3239 (10) nm 3, Dc = 1.775 g · cm -3, 6.967 mm -1, F (000) = 1672, R -1 = 0.0414 and wR 2 = 0.0988 Bis (3,5-dimethylpyrazol- 1 -yl) methane acts as a bridging bidentate ligand in this complex, which links two W CO) _5 fragments. In addition, heating this complex under reflux in 1,2-dimethoxyethane (DME) gi ves the known chelated mononuclear complex CH_2 (3,5-Me_2Pz) _2-W (CO) _4 (3).