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Fadila Balegroune Pierre Braunstein Laurent Douce Yves Dusausoy Daniel Grandjean Michael Knorr Martin Strampfer 《Journal of Cluster Science》1992,3(3):275-296
The reactions of K[Fe{Si(OMe)3}(CO)3(PY)][PY=Ph2PCH2C(O)Ph, Ph2PCH2C(O)[(-C5H4)FeCp] (Cp=5-C5H5), Ph2P(CH2)2CN] with CdCl2·2.5H2O, ZnX
2 (X=Cl, I) or InCl3 afforded Fe-Cd-Fe or Fe-M(-X)2
M-Fe (M=Cd, Zn, In;X=Cl, I) and Fe-InCl2 complexes. Some of them contain an unusual and labile -2-SiO alkoxysilyl bridge which may be associated with a bridging mode for the ketophosphine ligand (first such example structurally established), thus providing original results in bimetallic chemistry on the intramolecular coordination of oxygendonor functions ofchemically different hemilabile ligands firmly attached to a neighboring metal center. The structures of the trinuclear complex (3), of the chlorobenzene solvate of the tetranuclear complex (4a·C6H5Cl) and of [mer-(OC)3{(EtO)3Si} (4e) have been determined by X-ray diffraction. Crystals of 3 are orthorhombic, space groupPbcn, witha=19.010(4),b=11.766(5),c=26.998(7)Å, andZ=4. Crystals of4a·C6H5Cl are monoclinic, space groupC2/c witha=22.455(3),b=17.680(2),c=16.627(4)Å, =90.80(4)°, andZ=4. Crystals of4e are monoclinic, space groupC2/c witha=25.392(5),b=18.554(6),c=16.28(1)Å, =120.73(3)°, andZ=4. The structures were solved using direct methods and Fourier difference techniques and refined by blocked full-matrix least squares toR=0.035 (R
w
=0.049) for 2719 observed reflections, toR=0.042 (R
w
=0.056) for 3082 observed reflections, and toR=0.057 (R
w
=0.075) for 1850 observed reflections for3, 4a·C6H5Cl and4e, respectively. The Fe-Zn complexes (9a), (9b) and (9c) were prepared and characterized by spectroscopic methods.Part 21 in the Series: Complexes with Functional Phosphines. Part 20: P. Braunstein, S. Coco Cea, A. DeCian, and J. Fischer (1992).Inorg. Chem.
31, 4203. 相似文献
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Michael Knorr Isabelle Jourdain Carsten Strohmann 《Journal of organometallic chemistry》2005,690(6):1456-1466
Insertion of hexafluorobutyne into the Pt-H bond of the heterobimetallic complexes [(OC)3Fe{Si(OMe)3}(μ-Ph2PXPPh2)Pt(H)(PPh3)] (1a X = CH2; 1b X = NH) yields the σ-alkenyl complexes [(OC)3Fe{μ-Si(OMe)2(OMe)}(μ-Ph2PXPPh2)Pt{C(CF3)C(H)CF3}] (3a X = CH2; 3b X = NH). This insertion reaction is accompanied by dissociation of the platinum bound PPh3 ligand and saturation of the vacant coordination site by a dative μ−η2-Si-O → Pt interaction. Addition of the Pt-H bond of 1a across the triple bond of 3,3,3-trifluoropropyne affords in a regiospecific manner [(OC)3Fe{μ-Si(OMe)2(OMe)}(μ-dppm)Pt{C(CF3)CH2}] (2) having the trifluoromethyl substituent on the α-carbon. Addition of RNC to 3 affords the isocyanide adducts [(OC)3Fe{Si(OMe)3}(μ-Ph2PXPPh2)Pt(CNR){C(CF3)C(H)CF3}] (4a R = t-Bu, X = CH2; 4b R = 2,6-xylyl, X = CH2; 4c R = 2,6-xylyl, X = NH). In dichloromethane solution 3a is gradually transformed into the C4F6-bridged compound [(OC)3Fe(μ-dppm)(μ-CF3CCCF3)Pt(CO)] 5. The Pt-bound carbonyl ligand of 5 is displaced by xylylisocyanide or trimethylphosphite affording the derivatives [(OC)3Fe(μ-dppm)(μ-CF3CCCF3)Pt(CNxylyl)] 6 and [(OC)3Fe(μ-dppm)(μ-CF3CCCF3)Pt{P(OMe)3}] 7. The molecular structures of 4a, 5 and 6 have been determined by X-ray diffraction studies. 相似文献
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A cheap synthesis of the so‐called ‘decalin‐1,8‐diones’ started with the conjugate (1,4‐) addition of cyclohex‐2‐en‐1‐one derivatives to the γ‐position of the dilithium derivative (buta‐1,3‐diene‐1,1‐bis(olate)) of crotonic acid. Hydrogenation of these ‘1,4‐γ’ adducts and final cyclization afforded the enol tautomers of decalin‐1,8‐diones. Nucleophilic substitutions at these 3‐oxoenols by NH3 or primary amines created only monoamino products (namely, 3‐oxoenamines) whose reactions with OPCl3 yielded dihydro(1,3,2)oxazaphosphinin‐2‐one derivatives. The two regioisomers of a trimethyl‐3‐oxoenamine served as models for the constitutional assignments of the two rapidly interconverting (hence, individually NMR‐invisible), tautomeric trimethyl‐3‐oxoenols. Such methyl substitutions served to break the ‘pretended’ symmetry of ‘decalin‐1,8‐dione’. Hydrazine and 3‐oxoenols furnished oxygen‐free indazole derivatives whose N?H bonds exchanged with t1/2=ca. 0.00035 s at ca. ?58(9) °C. 相似文献
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