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Reactivity of 1,3-disubstituted indolyl compounds with lithium reagents was studied to reveal the substituents and solvent effects on coordination modes and reactivities resulting in different indolyl lithium complexes. Treatment of 1-alkyl-3-imino functionalized compounds 1-R-3-(R′N═CH)C8H5N [R = Bn, R′ = Dipp (HL1); R = Bn, R′ = tBu (HL2); R = CH3OCH2, R′ = Dipp (HL3); Dipp = iPr2C6H3] with Me3SiCH2Li or nBuLi in hydrocarbon solvents (toluene or n-hexane) produced 1,3-disubstituted-2-indolyl lithium complexes [η1:(μ2-η1:η1)-1-Bn-3-(DippN═CH)C8H4NLi]2 (1), {[η1:(μ3-η1:η1:η1)-1-Bn-3-(tBuN═CH)C8H4N][η2:η1:(μ2-η1:η1)-1-Bn-3-(tBuN═CH)C8H4N][η1:(μ2-η1:η1)-1-Bn-3-(tBuN═CH)C8H4N]Li3} (2), and [η1:η1:(μ2-η1:η1)-1-CH3OCH2-3-(DippN═CH)C8H4NLi]2 (3), respectively. The bonding modes of the indolyl ligand were kept in 1 by coordination with donor solvent, affording [η1:(μ2-η1:η1)-1-Bn-3-(DippN═CH)C8H4NLi(THF)]2 (4). The trinuclear complex 2 was converted to dinuclear form with a change of bonding modes of the indolyl...

Four new triply-bonded ditungsten complexes of the formula cis,cis-W2Cl4(NHCMe3)2(L-L) (L-L = dmpm (1), dmpe (2), dppm (3), dppe (4)) have been prepared by reaction of W2Cl4(NHCMe3)2(NH2CMe3)2 with the appropriate bidentate phosphines (L-L) in hydrocarbon solvents. These complexes are the first triply-bonded complexes of the form W2Cl4(NHR)2(L-L) where L-L groups are bidentate phosphines. The molecular structures have been investigated by X-ray crystallography. Crystal data are as follows: for 1, monoclinic space group P21/n, a = 13.807(1) A, b = 11.835(2) A, c = 15.348(1) A, β = 109.19(2)°, Z = 4; for 2, P21/n, a = 14.144(2) A, b = 11.991(1) A, c = 15.662(2) A, β = 109.50(1)°, Z = 4; for 3·CH2Cl2, P21/c, a = 18.777(6) A, b = 10.273(2) A, c = 21.082(3) A, β = 94.11(6)°, Z = 4; for 4, P21/n, a = 11.938(1) A, b = 18.583(3) A, c = 17.606(2) A, β = 106.54(6)°, Z = 4. The W−W bond lengths for 1, 2, 3·CH2Cl2, and 4 are 2.3247(4), 2.3274(5), 2.328(1), and 2.3452(5) A, respectively, which are consistent with a f...

Decomposition de VCl 5 en VCl 3 avec formation de Cl 2 ou du radical Cl. Cinetique de la reaction dans differents solvants, hydrocarbures satures ou olefines

Photochemistry of R3SiCo(CO)4 (R = Et, Ph) in hydrocarbon solvents shows that the dominant primary excited state process is loss of CO, not cleavage of the Si-Co bond. The 366 nm quantum yield for CO substitution by P(OPh)3 is 0.28 + or - 0.05 to give R3SiCo(CO)3P(OPh)3. Regeneration of catalytic activity in the Co2(CO)8/1-pentene/HSiEt3 system can be accomplished photochemically by exciting the Et3SiCo(CO)4 species.