Mono- and dimeric phosphine complexes of cyclopentadienylvanadium(II) halides

Abstract

Reduction of C P V X~(P R~)~ (X = C1, R = Me, Et; X = Br, R = Et) with A1 or Zn in THF gives dimeric vanadium(I1) complexes [CpVX(PR,)],. Methylcyclopentadienyl compounds are accessible by the same method. Treating the dimers with an exceas of PR, gives CpVx(PF&J,, and treating the dimers with bidentate phosphines, CpVCl(DMPE) and CpVCl(DPPE) are obtained. All compounds are paramagnetic with, in principle, three unpaired electrons on the metal atom. ' H NMR spectra of the complexes show large downfield shifts of the cyclopentadienyl protons (range of 64-250 ppm). The phosphine ligands show smaller shifts, varying between-3.0 and 4.60 ppm for the dimers [CpVX(PR3)], and between-25.5 and-17.0 ppm for CpVCl(DMPE). The complexes are very reactive and their reactions with a variety of substrates, e.g., dioxygen, cyclohexene oxide, alkynes, and carbon monoxide, proceed easily. With a-olefins no reaction (hydrogenation, isomerization, or oligomerization) was observed.

Chemistry of cyclopentadienylruthenium and -osmium complexes. 4. The facile synthesis of cyclopentadienylruthenium(IV) and -osmium(IV) allyl complexes and the characterization of a novel ruthenium(IV) intermediate in the dehydrohalogenation and dehydrogenation of 3-bromocyclohexene. The x-ray crystal structure of [(.eta.5-C5H5)Ru(.eta.3-C4H4OMe)Cl2]

“…[2 H, d, J(CH2HJ = 4.2, CH2C1], 3.92 [1 H, d, J(HCHJ = 10.1, HJ 7 7.45 (1 H, m, Ph), 7.39 (2 H, m, Ph), 7. 33 (2 H, m, Ph), 5.56 (5 H, s, C5H6), 5.43 [1 H, d, J(HC-HJ = 11.4, HJ, 5.29 [1 H, ddd, e/(HaHJ = 11.4, J(HaHJ = 9.8, =/(HaHJ = 6.2, HJ, 4.59 [1 H, d, J(HbHJ = 6.2, HJ, 3.84 [1 H, d, J(HCHJ = 9.8, HJ 8 5.76 (5 H, a, C6H6), 4.53 (2 H, a, HJ, 4.11 (2 H, a, HJ 9 5.66 (5 H, a, C5HJ, 5.01 [1 H, tt, J(HaHJ = 10.3, J(HaHJ = 6.2, HJ, 4.57 [2 H, d, J(HbHJ = 6.2, HJ, 3.52 [2 H, d, =/(HcHJ = 10.3, HJ 106 5.89 (5 H, a, C5HJ, 4.79 [1 H, td, «7(HaHJ = 10.2, J(HaHJ = 6.2, HJ, 4.50 (1 H, m, HJ, 4.41 [1 H, d, =/(HbHJ = 6.2, HJ, 3.99 [2 H, d, J(CH2HJ = 3.6, CHJ, 3.82 [1 H, d, =7(HCHJ = 10.2, HJ 11 5.76 (5 H, a, C5HJ, 4.53 (2 H, a, HJ, 4.11 (2 H, a, HJ 12 5.66 (5 H, a, C5HJ, 4.97 [1 H, tt, =/(HaHJ = 11.0, J(HaHJ = 6.0, HJ, 4.76 [2 H, d, J(HbHJ = 6.0, HJ, 3.21 [2 H, d, </(HcHJ = 11.0, HJ 13 5.47 (2 H, m, CJfJVle), 5.20 (2 H, m, Cg/iJMe), 5.04 [1 H, tt, J(HaHJ = 10.4, =7(HaHJ = 6.1, HJ, 4.37 [2 H, d, J(HbHJ = 6.1, HJ, 3.53 [2 H, d, «7(HCHJ = 10.4, HJ, 2.11 (3 H, a, Me) 14 5.35 (1 H, m, Cgff4Me), 5.32 (1 H, m, C^Me), 5.09 (2 H, m, C^Me), 4.78 [1 H, ddd, =/(HaHJ = 10.1, =Z(HaHJ = 10.0, J(HaHJ = 6.0, HJ, 4.36 [1 H, d, </(HbHJ = 6.0, HJ, 4.32 [1 H, dq, =/(Hc,HJ = 10.1, J(HJMe) = 6.3, HJ, 3.38 [1 H, d, </(HcHa) = 10.0, HJ, 2.06 (3 H, a, C6H4Me), 1.69 [3 H, d, J(MeHJ = 6.3, Me] 15 5.42 (2 H, m, C^Me), 5.19 (2 H, m, CgffJVie), 3.96 (2 H, a, HJ, 3.49 (2 H, a, HJ, 2.28 (3 H, a, MeJ, 2.09 (3 H, a, C6H4Me) 16 5.58 (1 H, m, C^Me), 5.44 (1 H, m, CJfJVIe), 5.25 (1 H, m, CgfiJMe), 5.21 (1 H, m, CjfJMe), 4.96 (1 H, m, HJ, 4.39 [1 H, d, J(HbHJ = 5.8, HJ, 4.21 (1 H, m, HJ, 4.08 [2 H, d, J(CH2HJ = 10.0, CH2C1], 3.46 [1 H, d, J(HCHJ = 10.1, HJ, 2.10 (3 H, a, Me) 17 7.43 (1 H, m, Ph), 7.39 (2 H, m, Ph), 7. 31 (2 H, m, Ph), 5.38 (1 H, m, HJ, 5.36 (1 H, m, Cg/iJMe), 5.33 (1 H, m, CJfJMe), 5.25 [1 H, d, «/(He-HJ = 11.3, HJ, 5.13 (2 H, m, CjH4Me), 4.50 [1 H, d, =/(HbHJ = 6.1, HJ, 3.65 [1 H, d, J(HCHJ = 9.2, HJ, 1.99…”

“…The organometallic chemistry of ruthenium in the lower (O, +1, and +11) oxidation states is well-established as one of the cornerstones of the coordination chemistry of this metal.1"3 In contrast, comparatively little is known of higher oxidation state organoruthenium chemistry,1"3 apparently despite a quite extensive inorganic chemistry of the +III to +VIII states,1 and also, the implication of high oxidation state organometallics in a range of rutheniumcatalyzed transformations of organic molecules including isomerization and dehydrogenation reactions.4 With particular regard to the ruthenium(IV) oxidation state, organometallic complexes appear to fall into certain 25.20 (25.49) 4 [(i)e-C5H6)Ru(ij3-C3H4Me-l)Cl2] red-orange 92 36.59 (36.99) 4.23 (4.14) 24.35 (24.27) 5 [(I,5-C6H6)Ru(^3-C3H4Me-2)Cl2] orange 92 36.92 (36.99) 4.21 (4.14) 24.35 (24.27) 6 [(7,5-C5H5)Ru(7,3-C3H4CH2C1-1)C12] orange 83 32.98 (33.09) 3. 23 (3.39) 32.27 (32.56) 7 [("6-C5H5)Ru(t3-C3H4Ph-l)Cl2] orange 90 47.66 (47.47) 4.06 (3.98) 20.11 (20.02) 8 [("5-C5H5)Ru("3-C3H4C1-2)C12] orange 86 30.48 (30.73) 2.62 (2.90) 34.42 (34.02) 9 [("5-C6H6)Ru("3-C3H5)Br2] red-orange 90 26.28 (26.18) 2.64 (2.75) 41.43 (43.54) 10 [(7,6-C5H6)Ru(u3-C3H4CH2Br-l)Br2] red-orange 94 23.26 (23.50) 2.38 (2.41) 52.60 (52.11) 11 [("5-C6H5)Ru("3-C3H4Br-2)Br2] red 84 21.69 (21.54) 1.91 (2.03) 54.…”

“…30 (53.43) 20 [(t5-C6H5)Ru("3-C4H4OMe)Cl2] red-orange 91 37.55 (37.51) 3.82 (3.78) 22.19 (22.14) 21 [(7,5-C5H6)Ru(»!3-C4H4OEt)Cl2] red-orange 90 39.54 (39.53) 4.20 (4.22) 21.29 (21.21) 22 [(,5-C6H5)Ru("3-C6H9)Br2] orange 84 31.68 (32.44) 3. 33 (3.46) 39.46 (39.25) 25 [("6-C5Me6)Os("3-C3H6)Cl2] yellow 43 36.98 (35.70) 4.71 (4.61) 15.20 (16.21) 26 [(,5-C6Me5)Os(7,3-C3H4Me-l)Cl2] yellow 53 37.09 (37.25) 4.78 (4.91) 15.93 (15.71) 27 [("5-C5Me5)Os("3-C3H4Me-2)CI2] yellow 47 37.06 (37.25) 5.04 (4.91) 15.65 (15.71) "None of complexes 3-22 and 25-27 melted below 250 °C. 6Found (calculated in parentheses).…”

Synthesis and Structure of Vanadium Halide Complexes Containing Diphosphine Ligands with Pendant Amines

“…S = 3/2 spin‐state. Similar high‐spin three‐legged piano‐stool vanadium(II) complexes containing traditional diphosphine ligands were reported by Teuben and co‐workers by Zn or Al reduction of trans ‐[CpVCl 2 (PMe 3 ) 2 ] (described above), to generate a dimeric halide‐bridged complex [CpVCl(PMe 3 )] 2 , from which the desired CpV(dmpe)Cl or CpV(dppe)Cl product was formed upon addition of the corresponding diphosphine ligand 21…”

Synthesis, Characterization, and Structural Studies of Transition Metal Open Fulvalene Complexes

“…Hydrocarbon and ethereal solvents were distilled from sodium/benzophenone ketyl under a nitrogen atmosphere, while methylene chloride was dried by distillation from P 4 O 10 under nitrogen, and nitromethane was dried for at least several days with molecular sieves prior to distillation under a nitrogen atmosphere. Co(C 5 H 5 )(C 2 H 4 ) 2 , [Ru(C 5 Me 5 )Cl] 4 , and V(C 5 H 5 )(Cl) 2 (PMe 3 ) 2 were prepared according to published procedures, except that in the preparation of V(C 5 H 5 )(Cl) 2 (PMe 3 ) 2 , NaC 5 H 5 was utilized instead of the magnesium reagent, and a 60:40 hexane/THF solvent mixture was used for extraction and crystallization. ESR spectra were obtained on samples having concentrations of ca.…”