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61.
A reaction of CpMn(CO)(NO)Sn(C=CPh)3 (I) with [Cp′Mo(CO)2]2 (Cp′ = MeC5H4) gave CpMn(CO)(NO)Sn(C=CPh)3[Cp′Mo(CO)2]2 (II) as dark red prismatic crystals. The molecular structure of complex II was determined by X-ray diffraction study. Complex II contains the Mo-Mo bond (2.9799(5) Å), which is perpendicular to the coordinated C=C bond. The latter is longer (1.371(5) Å) than free acetylenide fragments (1.190(5) and 1.198(5) Å). In addition, the angle Sn-C=C for the coordinated C=C bond is smaller (134.1(3)°) than that in free fragments (173.5(4)° and 171.9(4)°). The Mn-Sn bond length in complex II (2.5662(7) Å) is close to that in complexI (2.5328(17) Å) and is much shorter than the sum of the corresponding covalent radii (2.78 Å). The Sn-C bond (2.108(4) Å) in the acetylenide fragment π-bound to two Mo atoms (average Mo-C, 2.19 Å), as well as the other Sn-C bonds (2.119(4) and 2.135(4) Å), remains virtually the same as in complex I (average 2.105 Å).  相似文献   
62.
A number of stannylene complexes with different M: Sn ratios were obtained using various metals and substituents at the tin atom. The structures of the complexes were examined. A reaction of CpMn(CO)2THF with (Ph4As)+(SnCl3)? gave the ionic complex [Ph4As]+[CpMn(CO)2SnCl3]? (I). The action of C6F5MgBr on the complex C5H5Mn(CO)(NO)SnCl3 produced C5H5Mn(CO)(NO)Sn(C6F5)3 (II). Replacement of the Cl ions in the complex [CpFe(CO)2]2SnCl2 by phenylacetylenide groups gave rise to the neutral complex [CpFe(CO)2]2Sn(C≡CPh)2 (III). A reaction of (Dppm)PtCl2 (Dppm is 1,1-bis(diphenylphosphino)methane) with SnCl2 · 2H2O in the presence of diglyme yielded the ionic complex [η3-CH3O(CH2)2O(CH2)2OCH3)SnCl]+[(η 2-Dppm)Pt(SnCl3)3]? (IV). Transmetalation in a reaction of [(Dppe)2CoCl][SnCl3] · PhBr (Dppe is 1,2-bis(diphenylphosphino)ethane) with (Dcpd)PtCl2 (Dcpd is dicyclopentadiene) in the presence of SnCl2 afforded the ionic complex [Pt(Dppe)2]3[Pt(SnCl3)5]2 (V). Structures I–V were identified by X-ray diffraction. In these structures, the formally single bonds between the atoms of transition metals M (Mn, Fe, and Pt) and Main Group heavy elements (Sn and P) having vacant d orbitals are appreciably shortened. The M-Sn bond length in complexes II and III are virtually independent of the substituents at the tin atom and the Pt-Sn bond length in complexes IV and V is virtually independent of the Pt: Sn ratio.  相似文献   
63.
The heterometallic complex (CO)3(PPh3)Re(μ-SPr)Pt(PPh3)(CO) (I) was formed in the reaction of Re2(μ-SPr)2(CO)8 with (PPh3)2Pt(C2Ph2), together with (CO)3(PPh3)Re(μ-SPr)2Re(CO)4 (II), which was also prepared by an alternative synthesis. Compounds I and II were characterized by X-ray diffraction. In I, the Re-Pt single bond, 2.7414(5) Å, is supplemented by a thiolate bridge with shortened bonds: Pt-S (2.336(2) Å) and Re-S (2.449(2) Å). The Re-P (2.469(2) Å) and Pt-P (2.329(2) Å) bonds are also shortened. Complex II resulting from replacement of one CO group in the starting rhenium complex by triphenylphosphine has no M-M bond, and the Re-S and Re-P bond lengths (2.511(2)–2.527(2) and 2.517(3) Å) are close to the length of single bonds. It is assumed that the platinum atom in I is attached to the formally double bond Re ? SPr arising upon dissociation of Re2(μ-SPr)2(CO)8.  相似文献   
64.
The bromination of CpFe(CO)2TePh (I) affords the monomeric complex CpFe(CO)2TePhBr2 (II) as the major product and crystals (III), being a cocrystallizate of complexes II and CpFe(CO)2TeBrPh(μ-Br)TePhBr3 (IIIA). Complex IIIA contains a PhTeBr3 molecule, which is weakly bound because of the lone electron pair (LEP) of the bridging bromine atom of molecule II. An analogous weak interaction with the LEP of oxygen in tetrahydrofuran (Te…O 2.893 ?) is observed in the PhTeI3(THF) adduct (IV), which is a dimer with two bridging iodine atoms and can be obtained by the crystallization of PhTeI3 from THF. According to the X-ray diffraction data, the Fe-Te distances in compounds II and IIIA (on the average, 2.5 ?) differ slightly and are similarly shortened by 0.2 ? compared to the sum of the covalent radii of iron and tellurium. The secondary interactions Te…halide and Te…π system of the phenyl ligand are discussed. Original Russian Text ? Yu.V. Torubaev, A.A. Pasynskii, I.V. Skabitskii, 2009, published in Koordinatsionnaya Khimiya, 2009, Vol. 35, No. 5, pp. 347–352.  相似文献   
65.
The reaction of [Cp′Cr(CO)2(μ-SBu)]2 (1) (Cp′ = MeC5H4) with (PPh3)2Pt(PhCCPh) gives Cp′Cr(CO)2(μ-SBu)Pt(PPh3)2 (2) which could be regarded as a product of the substitution of acetylene ligand at platinum by a monomeric chromium-thiolate fragment. According to the X-ray diffraction analysis 2 contains single Cr-Pt (2.7538(15)) and Pt-S (2.294(2) Å) bonds while Cr-S bond (2.274(3) Å) is shortened in comparison with ordinary Cr-S bonds (2.4107(4)-2.4311(4) Å) in 1. The bonding between Cr-S fragment and platinum atom is similar to the olefine coordination in their platinum complexes.  相似文献   
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