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1.
Perfluoromethyl-Element-Ligands. XVIII. Preparation and Spectroscopic Investigation of M(CO)5L and M(CO)4L2 Complexes [L = MenP(CF3)3?n; n = 0–3; M = Cr, Mo, W] M(CO)5L and cis-M(CO)4L2 complexes, respectively [M = Cr, Mo, W; L = MenP(CF3)3?n; n = 0–3] are prepared reacting M(CO)5 · THF or M(CO)4norbor with L at room temperature. The cis-compounds isomerize above 50°C yielding the trans-complexes; the rate of isomerization increases with increasing number of CF3 groups. Thermal reaction of M(CO)6 (M = Cr, Mo, W) with P(CF3)3 yields M(CO)5P(CF3)3 and trans-M(CO)4[P(CF3)3]2. Introduction of three P(CF3)3 ligands by reaction with M(CO)3(cycloheptatriene) (M = Cr, Mo) proves unsuccessful; besides little M(CO)5P(CF3)3 trans-M(CO)4[P(CF3)3]2 is formed. The new compounds are characterized by analytical and spectroscopic (n.m.r., i.r., MS) methods.  相似文献   

2.
Preparation and spectroscopical Investigations of M(CO)4L2 and M(CO)3L3 Complexes (M = Cr, Mo, W; L = Me3SiOCH2PMe2, Me2(CH2?CH)SiOCH2PMe2 The coordinating properties of the ligands L1 (?Me3SiOCH2PMe2) and L2 (?Me2ViSiOCH2PMe2)1) have been studied by synthesis and spectroscopic investigations (IR, NMR, MS) of their complexes M(CO)4L2 and M(CO)3L3(M = Cr, Mo, W). The complexes are obtained by replacement of norbornadiene (NBD) in M(CO)4NBD or cycloheptatriene CHT in M(CO)3CHT. Spectroscopic data (v(CO), δ δ) support the σ-donor/-π-acceptor model of the MP bonds.  相似文献   

3.
Transition Metal-substituted Acylphosphanes and Phosphaalkenes. 22. Insertions of Hexafluoroacetone into the PX-Bond of Metallophosphanes (η5-C5Me5)(CO)2M? PX2 (M = Fe, Ru; X = Me3Si, Cl). Structure Determination of (η5-C5Me5)(CO)2Fe? P(SiMe3)C(CF3)2(OSiMe3) Reaction of the metallophosphanes (η5-C5Me5)(CO)2M? P(SiMe3)2 ( 1a : M = Fe; 1b : M = Ru) with hexafluoroacetone (HFA) afforded the complexes (η5-C5Me5)(CO)2M? P(SiMe3)C(CF3)2(OSiMe3) ( 2a, b ). The attempted synthesis of a metallophosphaalkene from 2a by thermal elimination of hexamethyldisiloxane failed. The acid catalyzed hydrolysis of 2a afforded compound (η5-C5Me5) · (CO)2Fe? P(H)C(CF3)2(OSiMe3) ( 3 ). Hexafluoracetone and (η5-C5Me5)(CO)2Fe? PCl2 ( 4 ) under-went reaction to give the metallochlorophosphan (η5-C5Me5) · (CO)2Fe? P(Cl)? O? C(CF3)2Cl ( 5 ). Constitutions and configurations of the compounds ( 2–5 ) were established by elemental analyses and spectroscopic data (IR, 1H-, 13C, 19F-, 29Si-, 31P-NMR, MS). The molecular structure of 2a was determined by x-ray diffraction analysis.  相似文献   

4.
Preparation and Properties of (CF3)2EMn(CO)5 (E ? P, As) The complexes (CF3)2EMn(CO)5 (E ? P, As) are formed by the reaction of E2(CF3)4 with HMn(CO)5. They can be converted quantitatively to the binuclear compounds [Mn(CO)4E(CF3)2]2 in a thermal (E ? P) or photochemical (E ? P, As) process. u. v. irradiation of a 1:1 mixture gives the mixed derivative Mn2(CO)8As(CF3)2P(CF3)2 together with the symmetrical systems. The Mn? E bond is less reactive with HBr and Me3SnBr than the M? E bond in derivatives of the type Me3ME(CF3)2 (M ? Si, Ge, Sn; Me ? CH3). The terminal (CF3)2E groups are found to be strong π-acceptor ligands.  相似文献   

5.
6.
Chelate Complexes of the Type M(CO)4(Me2XGeMe2CH2X′Me2) (M) = Cr, Mo, W; X, X′ = N, P, As; Me = CH3) The ligands (Me2)XGeMe2CH2X′Me2 (M) = Cr, Mo, W) react with M(CO)4norbor (norbor = Norbornadiene) (M = Cr, Mo, W) yielding the chelate complexes M(CO)4(Me)2XGeMe2CH2X′Me2). compounds of low thermal stability are formed with the ligands (Me2NGeMe2CH2X′Me2 because of the weak donor ability of the GeNMe2 group and with Me2AsGeMe2CH2NMe2 caused by strong steric ring tension. The new compounds are characterized by analytical and spectroscopic (n.m.r., i.r., m.s.) investigations.  相似文献   

7.
Co-ordinative Properties of Chelating Ligands of the Type Me2XSi(Me2)CH2XMe2 (X ? N and/or P; Me ? CH3) The reactions of the ligands L ? Me2XSi(Me2)CH2XMe2 (X ? N and/or P; Me ? CH3) with M(CO)6 and M(CO)4norbor (norbor ? norbornadiene) (M ? Cr, Mo), respectively, yield derivatives of the types M(CO)5L, M(CO)4L, and M(CO)4L2, respectively. M(CO)5L compounds are formed from the hexacarbonyls with Me2NSiMe2CH2PMe2, whereas the ligand Me2NSiMe2CH2NMe2 does not afford analogous derivatives under the same conditions. Even on substitution of the diene-ligand in M(CO)4norbor by Me2NSiMe2CH2PMe2 the chelate complexes M(CO)4NMe2SiMe2CH2PMe2 are not obtained, but the cis-disubstituted products M(CO)4[PMe2CH2SiMe2NMe2]2 with phosphorus acting as donor atom are produced. The ligands Me2PSiMe2CH2XMe2(X ? N, P) give the chelate complexes M(CO)4PMe2SiMe2CH2XMe2 in high yields. The new compounds were identified by analytical and spectroscopic (PMR, IR, mass spectra) methods.  相似文献   

8.
Perfluoromethyl Element Ligands. XLIII [1] Novel Synthetic Routes to Binuclear Complexes of the Type MM′(CO)8ER2X (M/M′ = Mn/Mn, Mn/Re, Re/Re; E = P, As; R = CF3, Me; X = Hal, ) Mn(CO)5I reacts with compounds of the type (CF3)2EAsMe2 (E = P, As) as with the symmetric E2(CF3)4 ligands in the first step with cleavage of the E‐As bond to yield the pro ducts (CO)5MnE(CF3)2 and Me2AsI. Reaction of the mononuclear complexes with excess of Mn(CO)5I leads in good yields to the known dinuclear compounds (CO)4Mn[E(CF3)2, I]Mn(CO)4 and CO. Me2AsI, the second product of the EAs cleavage, attacks the starting compound Mn(CO)5I giving cis‐Mn(CO)4I(AsMe2I) and CO. This result encouraged us to thoroughly investigate the preparation of cis‐M(CO)4X(EMe2Y) complexes with most of the possible combinations of M = Mn, Re; E = P, As and X, Y = Cl, Br, I. An alternative route to these compounds was opened by the cleavage of the dinuclear manganese or rhenium halides M2(CO)8X2 with the halophosphanes or ‐arsanes Me2EY. This route was found to be especially advantageous for the preparation of the rheniumcarbonyl precursors, since milder conditions than for the CO‐substitution in Re(CO)5X compounds are sufficient for the halogen‐bridged dinuclear complexes. Cis‐M(CO)4X(EMe2Y) complexes were used as precursors for the synthesis of novel homo‐ and heterodinuclear complexes of the type (CO)4M(EMe2, X)M′(CO)4 by reacting the EY function with transition metal carbonylates Kat[M′(CO)5] (Kat = Na, Bu4N, Ph4As). Thus the preparation of a wide range of complexes was possible, which before had been successfully prepared by the direct reaction of Mn2(CO)10 with Me2EX only in few cases, e. g. with Me2AsI. Spectroscopic investigations, using the CO valence frequencies and the 1H‐NMR data of the ligands EMe2Y or of the Me2E bridges, were applied to study the influence of the variables M, M′, E, X, Y and Kat on the reactivity of the mononuclear complexes and the bonding situation in both the mono‐ and the dinuclear systems. The new compounds were characterized by spectroscopic (IR, NMR, MS) and analytic methods (C, H).  相似文献   

9.
Syntheses and Characterizations of the First Tris and Tetrakis(trifluoromethyl) Palladates(II) and Platinates(II), [M(CF3)3(PPh3)] and [M(CF3)4]2— (M = Pd, Pt) Tris(trifluoromethyl)(triphenylphosphino)palladate(II) and platinate(II), [M(CF3)3PPh3], and the tetrakis(trifluoromethyl)metallates, [M(CF3)4]2— (M = Pd, Pt), are prepared from the reactions of [MCl2(PPh3)2] and Me3SiCF3 / [Me4N]F or [I(CF3)2] salts in good yields. [Me4N][M(CF3)3(PPh3)] crystallize isotypically in the orthorhombic space group Pnma (no. 62) with Z = 4. The NMR spectra of the new compounds are described.  相似文献   

10.
11.
W(CO)5L complexes (L = R2EER′2, R2EE′R; R, R′ = CH3, CF3; E = P, As; E′ = S, Se, Te) have been prepared by reaction of W(CO)5·THF with L at room temperature or by redistribution reaction of W(CO)5E2Me4 with E2(CF3)4 or E′2Me2 as well as by cleavage of E2(CF3)4 with W(CO)5EMe2H. The new compounds were characterized by analytical and spectroscopic (IR, NMR, MS) methods; by comparison with of the data of free and coordinated ligands the effects of complexation are studied.  相似文献   

12.
Alternative Ligands. XXVI. M(CO)4 L-Complexes (M ? Cr, Mo, W) of the Chelating Ligands Me2ESiMe2(CH2)2E′ Me2 (Me ? CH3; E ? P, As; E′ ? N, P, As) The reaction of M(CO)4NBD (NBD = norbornadiene; M ? Cr, Mo, W) with the ligands Me2ESiMe2(CH2)2E′ Me2 yields the chelate complexes (CO)4M[Me2ESiMe2]) for E,E′ ? P, As, but not for E and /or E′ ? N. The NSi group is not suited for coordination because of strong (p-d)π-interaction. In the case of the ligands with E ? P or As and E′ ? N chelate complexes can be detected in the reaction mixture, but isolable products are complexes with two ligands coordinated via the E donor group. The new compounds are characterized by analytical and spectroscopic (IR, NMR, MS) investigations. The spectroscopic data are also used to deduce the coordinating properties of the ligands. X-ray diffraction studies of the molybdenum complexes (CO)4Mo[Me2ESiMe2(CH2)2AsMe 2] (E ? P, As) in accord with the observed coordination effects show only small differences between SiE and CE donor functions. Attempts to use the ligands Me2ESiMe2(CH2)2AsMe2 (E ? P, As) for the preparation of Fe(CO)3L complexes result in the fission of the SiE bonds and the formation of the binuclear systems Fe2(CO)6(EMe2)2 (E ? P, As) together with the disilane derivative [Me2Si(CH2)2AsMe2]2.  相似文献   

13.
The reaction of [Cp(CO)(dppm)Fe]BF4 (1a) with the phosphorus ylide Me3PCH2 yields the novel bis(phosphino)methanideiron complex Cp(CO)Fe(Ph2PCHPPh2) (2), which upon photolysis in the presnece of Me3P is converted into Cp(Me3P)Fe(Ph2PCHPPh2 (3). Reaction of 2 with MeOSO2CF3 gives a mixture of the iron salts [(Cp(CO)Fe(Ph2PCR(R′)PPh2)]CF3SO3 (R = R′ = H (1b), R = R′ = Me (6) and R = H, R′ = Me (syn/anti-4)).  相似文献   

14.
Bis‐trimethylamine‐ethynyl‐di‐bis(trifluoromethyl)borane [Me3N(CF3)2BCCB(CF3)2NMe3] ( 1 ) has been prepared from trimethylamine‐ethynyl‐bis(trifluoromethyl)borane, [HCCB(CF3)2NMe3], and dimethylamino‐bis(trifluoromethyl)borane, (CF3)2BNMe2. The structure of 1 has been determined by x‐ray crystallography. In the solid state the molecule possesses crystallographic Ci symmetry. The acetylenic attachment to the boron atom is characterized by a short B–C bond length of 1.565(4) Å and an essentially linear B–C–C′ bond angle of 178.1(4)°.  相似文献   

15.
16.
Perfluoroalkyl Tellurium Compounds: Investigations of the Preparation of [(CF3)2TeX]+ Cations and [(CF3)2TeX2+n]n? Anions (X = F, Cl, Br) The reactions of (CF3)2TeF2 with BF3, AsF5 and SbF5 yield the new complex compounds [(CF3)2TeF][BF4] and [(CF3)2TeF][EF6], respectively, while during the reactions of (CF3)2TeX2 (X = Cl, Br) with halide acceptors only decompositions take place. (CF3)2TeX2 form with MX (X = F, Cl; M = K, Rb, Cs, Me4N, Ag) the isolable salts of the composition M[(CF3)2TeX3]. M[(CF3)2TeBr3] is only detected in solution besides decomposition products. No evidence for the formation of hexa-coordinated tellurates(IV) M2[(CF3)2TeX4] is found.  相似文献   

17.
Perfluoromethyl-Element-Ligands. XVII. Formation of Adducts of MenE(CF3)3?n Ligands with BX3 Compounds (Me = CH3; E = P, As, Sb; n = 0–3; X = H, CH3, Hal) The ligands MenE(CF3)3?n (Me = CH3; E = P, As, Sb; n = 0–3) have been prepared (partly using new methods) and studied by n.m.r. spectroscopy (1H, 19F, 31P, 13C). In order to deduce their relative donor strength their reactions with the Lewis acids “BH3”, BMe3, BMe3, Me2BBr, and BX3 (X = F, Cl, Br) have been studied. Control of adduct formation occurs by n.m.r. spectroscopy (1H, 19F). The following series of decreasing basicity or acidity are obtained:   相似文献   

18.
Syntheses and Crystal Structures of the Phosphaneimine Complexes MCl2(Me3SiNPMe3)2 with M = Zn and Co, and CoCl2(HNPMe3)2 The molecular complexes MCl2(Me3SiNPMe3)2 (M = Zn, Co) have been prepared by the reaction of the dichlorides of zinc and cobalt with Me3SiNPMe3 in CH3CN and CH2Cl2, respectively, whereas the complex CoCl2(HNPMe3)2 has been prepared by the reaction of CoCl2 with NaF in boiling acetonitrile in the presence of Me3SiNPMe3. All complexes were characterized by IR spectroscopy and by crystal structure determinations. The complexes MCl2(Me3SiNPMe3)2 crystallize isotypically. ZnCl2(Me3SiNPMe3)2: Space group P212121, Z = 4, 2677 observed unique reflections, R = 0.024. Lattice dimensions at ?70°C: a = 1243.6; b = 1319.0; c = 1464.7 pm. CoCl2(Me3SiNPMe3)2: Space group P212121, Z = 4, 3963 observed unique reflections, R = 0,071. Lattice dimensions at ?80°C: a = 1236.3; b = 1317.4; c = 1457.6 pm. CoCl2(HNPMe3)2 · CH2Cl2: Space group Pbca, Z = 8, 1354 observed unique reflections, R = 0.055. Lattice dimensions at ?80°C: a = 1247.3; b = 998.4; c = 2882.4 pm. All complexes have monomeric molecular structures, in which the metal atoms are coordinated in a distorted tetrahedral fashion by the two chlorine atoms and by the nitrogen atoms of the phosphaneimine molecules.  相似文献   

19.
The compounds [2-(Me2NCH2)C6H4]2SbL (L = ONO2 ( 2 ), OSO2CF3 ( 3 )) and [PhCH2N(CH2C6H4)2]SbL (L = ONO2 ( 5 ), OSO2CF3 ( 6 )) were prepared by reacting [2-(Me2NCH2)C6H4]2SbCl ( 1 ) and [PhCH2N(CH2C6H4)2]SbCl ( 4 ), respectively, with the appropriate silver(I) salt in a 1:1 molar ratio. The new species 2 – 6 were structurally characterized in solution using multinuclear NMR and in the solid state using infrared spectroscopy. The solid-state structures for compounds 2 , 4 and 6, as well as for the hydrolysis ionic product [{2-(Me2N+HCH2)C6H4}{2-(Me2NCH2)C6H4}SbOH][CF3SO3] ( 3h ) were determined using single-crystal X-ray diffraction. Medium to strong intramolecular N→ Sb interactions were observed in all these four compounds, thus resulting in hypercoordinated organoantimony(III) species 14-Sb-6 in 2 and 10-Sb-4 in the cation of 3h and in 4 and 6 . Compounds 1 – 6 and the starting amines PhCH2NMe2 and PhCH2N(CH2C6H4Br-2)2 were investigated as catalysts in the Henry (nitroaldol) addition of nitromethane to benzaldehyde. The activity of compounds 1 – 6 resulted as an effect of the cooperation of the positively charged antimony with the negatively charged nitrogen.  相似文献   

20.
The electron impact induced mass spectra of [CF3SMn(CO)4]2, [CF3SeMn(CO)4]2, [CF3SFe(CO)3]2, [CF3SeFe(CO)3]2, CF3SeFe(CO)2C5H5 and CF3SCr(NO)2C5H5 are reported. These compounds exhibit weak molecular ion peaks and undergo preferential loss of CO or NO groups. The CO or NO free fragments suffer typical loss of ECF2(E = S, Se) with the simultaneous shift of F from carbon to metal. The ions [FFeC5H5]+ and [FCrC5H5]+ in the spectra of the cyclopentadienyl compounds prefer expulsion of π-cyclopentadienyls. The pyrolysis effects on the spectra of the compounds have been studied. An increase in temperature eases the expulsion of ECF2 groups from all the compounds and favors the formation of [Fe(C5H5)2]+ and [Cr(C5H5)2]+ in the cyclopentadienyl compounds.  相似文献   

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