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1.
Formation of Organosilicon Compounds. 109. Reactions of Perhydrogenated Carbosilanes with Alkyl-Lithium Compounds Si-hydrogenated linear carbosilanes react with MeLi or nBuLi to give the Si-alkylated derivatives. In contrast to the Si-methylated derivatives of (H3Si? CH2)2SiH2 1 and (H3Si)2CH2 2 and to (Me2Si? CH2)3 no lithiation of CH2 groups is observed. Such, 1 with nBuLi yields nBuH2Si? CH2? SiH2? CH2? SiH3 5 and (nBuH2Si? CH2)2SiH2 6 . 2 reacts with nBuLi to give nBuH2Si? CH2SiH3 7 and (nBuH2Si)2CH2 8 besides of 1, 5 und 6 . The latter results from a cleavage of a Si? C bond in 2 Producing nBuSiH3 and LiCH2? SiH3 which combines with 2 to 1 . Subsequently 1 forms 5 and 6 . No higher alkylated derivatives of 1 or 2 could be detected.  相似文献   

2.
Heteronuclear Coordination Compounds with Metal—Metal Bonds. IX. Amine Copper(I) Carbonyl Metalates with Cobalt, Iron, or Manganese Colourless crystals of the carbonyl copper complex [(NH3)3(CO)Cu][Co(CO)4] ( 1 a ) are formed in the reaction of [Cu(NH3)4]Cl and Na[Co(CO)4] (T < ? 8°C, pCO = 1 bar); above ?5°C and under N2-atmosphere 1 a converts to [(NH3)2CuCo(CO)4] ( C ), which serves as a starting material for the synthesis of new copper cobaltates: the amines N-amino piperidine, N,N-dimethyl ethylenediamine (dmed) and N-benzyl N,N′-dimethyl ethylenediamine (bn-dmed) replace NH3 to form [(C5H10N? NH2)3CuCo(CO)4] ( 1 b ), [(dmed)CuCo(CO)4] ( 1 c ), [(bn-dmed)CuCo(CO)4] ( 1 d ) the Cu? Co-bond remaining intact. [(NH3)2CuFe(CO)3NO] ( 2 a ) is isosteric with C ; it is synthesized from [Cu(NH3)4]Cl and Na[Fe(CO)3NO] in aqueous solution; 2 a reacts with N,N,N′,N′-tetramethyl ethylenediamine (tmed) to form [(tmed)(NH3)CuFe(CO)3NO] ( 2b ). The [Mn(CO)5]? ion reacts with ammine copper ions to form the tetranuclear cluster [{(NH3)CuMn(CO)5}2] ( 3 ). All new compounds have been investigated by X-ray structure analysis.  相似文献   

3.
The molecular geometries of three conformations of methyl propanoate (MEP) (C? C? C?O torsions of 0°, 120°, and 180°) and the potential-energy surfaces of MEP (C? C? C?O torsions) and of the methyl ester of glycine (MEG) (N? C? C?O torsions) have been determined by ab initio gradient calculations at the 4-21G level. MEP has conformational energy minima at 0° and 120° of the C? C? C?O torsion, while the 60–90° range and 180° are energy maxima. For MEG there are two minima (at 0° and 180°) and one barrier to N? C? C?O rotation in the 60–90° range. The N? C? C?O barrier height is about twice as high (4 kcal/mol) as the C? C? C?O barrier. The 180° N? C? C?O minimum is characteristically wide and flat allowing for considerable flexibility of the N? C? C?O torsion in the 150–210° range. This flexibility could be of potential importance for polypeptide systems, since the N? C? C?O angles of helical forms are usually found in this region. The molecular structures of the methyl ester group CH3OC(?O)CHRR′ in several systems are compared and found to be rather constant when R ? H and R′ ? H, CH3, CH3CH2; or when R ? NH2 and R′ ? H, CH3, or CH(CH3)2.  相似文献   

4.
On Chalcogenolates. 174. Reaction of Acetamidine with Carbon Disulfide. 3. Crystal Structure of Acetamidinium N-Acetimidoyl Dithiocarbamate The title compound [(H2N)2C? CH3][S2C? N?C(CH3)? NH2] crystallizes with Z = 4 in the monoclinic space group P21/n with cell dimensions a = 10.354(1), b = 6.798(1), c = 14.013(1) Å, β = 103.32(1)°. The crystal structure has been determined from single crystal X-ray data measured at 20°C and refined to a conventional R of 0.049 for 2 521 independent reflections (Rw = 0.052). The cation is associated with one anion by hydrogen bridges S…H? N and N…H? N forming an 8-membered ring system. The anion is not plane in contrast to hitherto known structures of dithiocarbamates.  相似文献   

5.
Formation of Organosilicon Compounds. 98. Reaction of Silylated Phosphorus Ylides with PCl3 The reaction of Si-substituted phosphorus ylides as Me2Si(CH2? SiMe2)2C?PMe3Br 1 , Cl2Si(CH2? SiCl2)2C?PMe2Cl 2 , and (Cl3Si)2C?PMe2Cl 3 with PCl3 yields (Cl2P)2C?PMe2Cl 5 by chlorinating cleavage of the Si-ylid-C bond. Besides 5 also (ClMe2SiCH2)2SiMe2, (Cl3SiCH2)2SiCl2, resp. SiCl4 result from the reaction of 1, 2 and 3 with PCl3. (Cl2P)2C?PMe2Cl forms colourless crystals, mp. 84°C.  相似文献   

6.
On Chalcogenolates. 113. Reactions of Chloramine with Carbon Disulfide and with Methylesters of Dithiocarbamic Acids The reactions of chloramine with CS2 and with H2N? CS? SCH3, CH3? NH? CS? SCH3, and (CH3)2N? CS? SCH3 have been studied. The reaction with the methylester of dithiocarbamic acid gives the known dimethyl perthiocyanate and the reaction with the methylester of N-methyldithiocarbamic acid leads to CH3S? CS? N(CH3)? C(?NCH3)? SCH3. The latter compound has been characterized by means of electron absorption spectra, infrared spectra, nuclear magnetic resonance spectra (1H and 13C), and mass spectra.  相似文献   

7.
3-Aminopropanol reacts with aryl(or aralkyl or alkyl)isothiocyanates R? N?C?S to yield the corresponding thio-ureas R? NH? CS? NH? (CH2)3OH which, refluxed with hydrochloric acid, are cyclized by elimination of water. The cyclization products are identical with the hydrothiazines resulting by elimination of sulfate or phosphate from the sulfuric or phosphoric monoesters of these thio-ureas. The resulting hydrothiazines are either 2-(R-imino)-tetrahydro-m-thiazines (I) or 2-(R-amino)-dihydro-Δ2-m-thiazines (II). Their structure has been established by comparison of their spectra with those of model compounds in one of which the C?N double bond is certainly endocyclic (2-methyl-dihydro-Δ2-m-thiazine), the other presenting an exocyclic C?N double bond (3-methyl-2-phenylimino-tetrahydro-m-thiazine). When R is an aryl group, the C?N double bond is exocyclic (structure I with >C?N? Ar), and one may presume that this structure is stabilized by resonance. When R is an aralkyl or an alkyl group, the C?N double bond is endocyclic (structure II). The nmr spectra were taken with three types of solvent: CDCl3 or CCl4; (CD3)2SO; CF3COOH. In CF3COOH solution the benzylic protons of the hydrothiazine with R = pF? C6H4CH2? couple with NH (J=5,5cps) which confirms the endocyclic position of the C?N double bond in this case.  相似文献   

8.
Synthesis and Properties of Partially Silylated Tri- and Tetraphosphanes. Reaction of Lithiated Diphosphanes with Chlorophosphanes The reactions of Li(Me3Si)P? P(SiMe3)(CMe3) 1 , Li(Me3Si)P? P(CMe3)2 2 , and Li(Me3C)P? P(SiMe3)(CMe3) 3 with the chlorophosphanes P(SiMe3)(CMe3)Cl, P(CMe3)2Cl, or P(CMe3)Cl2 generate the triphosphanes [(Me3C)(Me3Si)P]2P(SiMe3) 4 , (Me3C)(Me3Si)P? P(SiMe3)? P(CMe3)2 6 , [(Me3C)2P]2P(SiMe3) 7 , and (Me3C)(Me3Si)P? P(SiMe3)? P(CMe3)Cl 8 . The triphosphane (Me3C)2P? P(SiMe3)? P(SiMe3)2 5 is not obtainable as easily. The access to 5 starts by reacting PCl3 with P(SiMe3)(CMe3)2, forming (Me3C)2 P? PCl2, which then with LiP(SiMe3)2 gives (Me3C)2 P? P(Cl)? P(SiMe3)2 11 . Treating 11 with LiCMe3 generates (Me3C)2P? P(H)? P(SiMe3)2 16 , which can be lithiated by LiBu to give (Me3C)2P? P(Li)? P(SiMe3)2 13 and after reacting with Me3SiCl, finally yields 5 . 8 is stable at ?70°C and undergoes cyclization to P3(SiMe3)(CMe3)2 in the course of warming to ambient temperature, while Me3SiCl is split off. 7 , reacting with MeOH, forms [(Me3C)2P]2PH. (Me3C)2P? P(Li)? P(SiMe3)2 18 , which can be obtained by the reaction of 5 with LiBu, decomposes forming (Me3C)2P? P(Li)(SiMe3), P(SiMe3)3, and LiP(SiMe3)2, in contrast to either (Me3C)2P? P(Li)? P(SiMe3)(CMe3) 19 or [(Me3C)2P]2PLi, which are stable in ether solutions. The Li phosphides 1 , 2 , and 3 with BrH2C? CH2Br form the n-tetraphosphanes (Me3C)(Me3Si)P? [P(SiMe3)]2? P(SiMe3)(CMe3) 23 , (Me3C)2P? [P(SiMe3)]2? P(CMe3)2 24 , and (Me3C)(Me3Si)P? [P(CMe3)]2? P(SiMe3)(CMe3) 25 , respectively. Li(Me3Si)P? P(SiMe3)2, likewise, generates (Me3Si)2P? [P(SiMe3)]2? P(SiMe3)2 26 . Just as the n-triphosphanes 4 , 5 , 6 , and 7 , the n-tetraphosphanes 23 , 24 , and 25 can be isolated as crystalline compounds. 23 , treated with LiBu, does nor form any stable n-tetraphosphides, whereas 24 yields (Me3C)2P? P(Li)? P(SiMe3)? P(CMe3)2, that is stable in ethers. With MeOH, 24 , forms crystals of (Me3C)2P? P(H)? P(SiMe3)? P(CMe3)2.  相似文献   

9.
La4B14O27: A Lanthanum ultra‐Oxoborate with a Framework Structure Single crystals of La4B14O27 could be synthesized by the reaction of La2O3, LaCl3 and B2O3 with an access of CsCl as fluxing agent in gastightly sealed platinum ampoules within twenty days at 710 °C and appear as colourless, transparent and waterresistant platelets. The new lanthanum oxoborate La4B14O27 (monoclinic, C2/c; a = 1120.84(9), b = 641.98(6), c = 2537.2(2) pm, β = 100.125(8)°; Z = 4) is built of a three‐dimensional boron‐oxygen framework containing seven crystallographically different boron atoms. Four of these B3+ cations are surrounded by four O2? anions tetrahedrally, whereas the other three have only three oxygen neighbours with nearly plane triangular coordination figures. Three of the [BO4]5? tetrahedra form [B3O9]9? rings by cyclic vertex‐condensation, which are further linked via [BO3]3? units to infinite layers. Two of these layers connect via one [B2O7]8? unit of two corner‐shared [BO4]5? tetrahedra to double layers, which themselves build up a three‐dimensional framework together with chains consisting of two [BO4]5? tetrahedra and one [BO3]3? triangle. One of the two crystallographically independent La3+ cations (La1) is surrounded by ten O2? anions and resides within the oxoborate double layers. (La2)3+ shows a (8+2)‐fold coordination of O2? anions and occupies channels along the [110] direction.  相似文献   

10.
Reactions of Undecacarbonyl(acetonitrile)triiron with Alkyne Ethers (CO)11(CH3CN) 1 reacts with the alkyne ethers H3C? C?C? OC2H5 2a , H? C?C? OC2H5 2b , H3C? O? CH2? C?C? CH2? O? CH3, 2c and H3C? O? C(CH3)H? C?C? C(CH3)H? O? CH3 2d forming different cluster products depending on the substituents and the reaction conditions. The product obtained with 2a is the bisalkylidyne cluster Fe3(CO)9(m?3-C? CH3)(m?3-C? OC2H5) 3 which results from the cleavage of the carbon carbon triple bond. The alkyne 2b however yields the vinylidene cluster Fe3(CO)10(m?32-C? C(H)OC2H5) 4 by 1,2 proton shift. The alkyne clusters Fe3(CO)10(m?32-C? C(H)OC2H5) 4 by 1,2 proton shift. The alkyne clusters Fe3(CO)10(m?32- H3 C? O? CH2? C?C? CH2? O? CH3) 6 and Fe3(CO)9(m?-η2-H3C? O? CH2? C?C? CH2? O? CH3) 7 are the isolated products obtained from 2c . Thermolysis of 7 results in the formation of the dinuclear butatrien complex Fe2(CO)6 (H2C? C? C? CH2) 8a . The analogous compound Fe2(CO)6[H(H3C)C ? C ? C ? C(CH3)H] 8b is the only product of 2d and 1 . The structures of 4, 5 , and 6 have been determined by crystal structure determinations.  相似文献   

11.
On Chalcogenolates. 170. Reaction of N,N′-Diphenyl Formamidine with Carbon Disulfide 3. Crystal Structure of Potassium N,N′-Diphenyl N-Formimidoyl Dithiocarbamate · Dioxane The title compound K[S2C? N(C6H5)? CH?NC6H5] · C4H8O2 crystallizes with Z = 4 in the monoclinic space group P21/a with cell dimensions a = 10.703(2) Å, b = 18.068(3) Å, c = 10.504(3) Å, β = 100.96(3)°. The crystal structure has been determined from single crystal X-ray data measured at 20°C and refined to a conventional R of 0.052 for 4556 independent reflections (Rw = 0.054). The K+ cation is surrounded of one oxygen, one nitrogen, and three sulfur atoms to form a distorted trigonal bipyramid. The S2CNCN part of the anion, which exists as E, E conformer, is plane. The dioxane molecule has chair conformation without symmetry centre.  相似文献   

12.
Structural Chemistry of Phosphorus-containing Chains and Rings. 1. Crystal Structure of the Diphosphasilirane (t-BuP)2SiPh2 The three-membered P2Si-heterocycle 1, 2-di-tert-butyl-3, 3-diphenyl-1, 2, 3-diphosphasilirane (t-BuP)2SiPh2 crystallizes monoclinic in the space group P21 with a = 1041.2 pm, b = 882.3 pm, c = 1158.1 pm, β = 91.33° and Z = 2 formula units. A special structural feature is the regular triangle built up by two P and one Si. Therefore the endocyclic bond angle at Si is as low as 60°. The average bond lengths are P? P = 222.6 pm, P? Si = 222.5 pm, P? C = 190.8 pm, Si? C = 186.6 pm, (C? C )ph = 139.0 pm, ( C? C )t-Bu = 151.7 pm. The geometry of the substituents phenyl and tert-butyl is quite normal, the last ones are slightly disordered.  相似文献   

13.
Synthesis and Molecular Structure of Two 1-Sila-3-alanata-cyclobutane Derivatives with Four-membered AlC2Si-Heterocycles The C? H acidic bis(trimethylsilyl)methyl compounds Me3C? AlR2 und Me3C? CH2? AlR2 (R ? CH(SiMe3)2) are deprotonated by treatment with the sterically high shielded base LiCH(SiMe3)2 in the presence of 1,3,5-trimethylhexahydrotriazinane. The deprotonation occurs at a methyl group of one of the element-organic substituents, and the formed carbanions are stabilized by coordination to the unsaturated Al atoms yielding four-membered heterocycles. Both products were characterized by a crystal structure determination each showing bent ring systems.  相似文献   

14.
1,3-Dipoles with a Central S-Atom from the Reaction of Azides and Thiocarbonyl Compounds: An Unexpected MeS Migration in the Trapping Product of a ‘Thiocarbonyl-aminide’ with Methyl Dithiobenzoate Reaction of PhN3 with O-methyl thiobenzoate ( 11a ) and thioacetate ( 11c ) as well as with the dithio esters 11b,d at 80° yields the corresponding imidates and thioimidates 12 (Scheme 3). The formation of 12 is rationalized by a 1,3-dipolar cycloaddition of the azide and the C?S group followed by successive elimination of N2 and S. In the three-component reaction of 11b , PhN3, and the sterically crowded thioketone 1a , 1,2,4-trithiolane 13a and 1,4,2-dithiazolidine 3a are formed in addition to 12b (Scheme 4). The heterocycles 13a and 3a are trapping products of 1a and ‘thiocarbonyl-thiolate’ 5a and ‘thiocarbonyl-aminide’ 2a (Ar?Ph), respectively (Scheme 6). These 1,3-dipoles are formed as reactive intermediates. Surprisingly, in the presence of catalytic amounts of acids, the major product is the (methyldithio)cyclobutyl thioimidate of type 14 (Scheme 5), formed by an acid-catalyzed MeS migration in dithiazolidine 17 . A reaction mechanism is proposed in Scheme 7.  相似文献   

15.
Chemistry of Polyfunctional Molecules. 119 [1]. Tetracarbonyl-dicobalt-tetrahedrane Complexes with the Ligands Bis(diphenylphosphanyl)-amine, 2-Butin-1,4-diol, and tert.-Butylphosphaacetylene — Crystal Structure of the Phosphaalkyne Derivative Co2(μ-CO)2(CO)4(μ-Ph2P? NH? PPh2P,P′) · 1/2C6H5CH3 ( 4 · 1/2C6H5CH3) reacts with 2-butine-1,4-diol, HOCH2? C?C? CH2OH ( 5 ), to the dark-red tetrahedrane complex Co2(CO)4(μ-η22-HOCH2? C?C? CH2OH? C2, C3) · (μ-Ph2P? NH? PPh2? P,P′) · THF (6 · THF). With t-butyl-phosphaacetylene, tBu? C?P ( 7 ), 4 · THF forms Co2(CO)4(μ-η22-tBu? C?P)(μ-Ph2P? NH? PPh2? P,P′) ( 8 ), which also belongs to the tetrahydrane type. The compounds were characterized by their mass, IR, 31P{1H} NMR, 13C{1H} NMR, and1H NMR spectra. Crystals suitable for X-ray structure analyses have been obtained for 8 from dioxane. The dark red blocks crystallize in the monoclinic P21/c space group with the lattice constants a = 1404,1(5), b = 1330,0(7), c = 2578,8(10)pm; β = 90,82(3)°.  相似文献   

16.
Reaction of the Two-component System Triethylphosphite/Carbon Tetrachloride with Nucleophiles Containing Hydrogen. 1. Reaction with Acyl Amides Acyl amides react with the two-component system triethylphosphite/carbon tetrachloride yielding N-acyl phosphazenes, (EtO)3P?N? Ac. In this way (EtO)3P?N? P(O)(OEt)2, (EtO)3P?N? CN, (EtO)3P?N? C(O)Ph, and (EtO)3P?N? SO2Ph were prepared. Ethyl esters of phosphoric acid and trichloromethane phosphonic acid were obtained as by-products.  相似文献   

17.
The C3H6 has been investigated ab initio, taking all 24 electrons into account, using the Allgemeines Programmsystem/SCF ? MO ? LC (LCGO ) Methode. Variation of the C? C distance gives a total energy of ?116.02 a.u. at a C? C distance of 2.91 a.u. The ionization energy was found to be 10.33 eV.  相似文献   

18.
Contributions to the Chemistry of Phosphorus. 159. On the Reaction of the Diphosphaborirane (t-BuP)2BN(i-Pr)2 with Potassium or Potassium Naphthalenide The reaction of (t-BuP)2BN(i-Pr)2 with potassium or K-naphthalenide in tetrahydrofuran leads to K(t-Bu)P? ;BN(i-Pr)2? P(t-Bu)K ( 1 ) via P? ;P bond cleavage of the three-membered ring skeleton. Above ? 78°C 1 changes into the asymmetric compound K(t-Bu)P? ;P(t-Bu)? BHN(i-Pr)2 ( 2 ). In dimethoxyethane additionally the monometallated diphosphaborirane K(t-Bu)P2BN(i-Pr)2 ( 3 ) is formed. 1 and 3 , which could be isolated free from other phosphorus containing compounds, as well as the corresponding silylphosphanes Me3Si(t-Bu)P? ;BN(i-Pr)2? ;P(t-Bu)SiMe 3 ( 4 ) and Me3Si(t-Bu)P2BN(i-Pr)2 ( 5 ) were characterized by NMR spectroscopy. Protolysis of 3 or 5 leads to a decomposition of the three-membered ring skeleton with formation of H(t-Bu)P? ;PH2.  相似文献   

19.
The (CH3)+ has been investigated ab initio, taking all 8 electrons into account, using the Allgemeines Programmsystem/SCF ? MO ? LC (LCGO ) Verfahren. After varying the C? H distance and the position of the C atom, it was found that the (CH3)+ ion is planar with a bond distance of RCH = 2.05 a.u. The force constants (C? H stretching, angular vibration) were computed to be k1 = 18.9 mdyn/Å, and the associated frequencies to be ω1 = 3256 cm?1 and ω2 = 1526 cm?1. The ionization energy was found to be I = 25.75 eV. The electron affinity was estimated to be A = 5.4 eV.  相似文献   

20.
Reaction of Thiazylfluoride with Multifunctional Nitrogen Derivatives From the reaction of NSF 1 with LiN(SiMe3)R′ (R′ = CMe3, SiMe3), linear [e. g. (Me3C? N?S?N? )2S ( 11 ), Me3C? N?S?N? CMe3 ( 14 ), Me3Si? N?S?N? SiMe3 ( 17 ), (Me3Si)2N? S? N?S?N? SiMe3 ( 19 )] and cyclic thiazenes (S4N5F ( 22 )) are isolated, (S3N4)n ( 23 ) is obtained in high yield from 1 and 17 (in the ratio 2:1). Possible structures for 23 are discussed; the reaction of 23 with AsF5 gives S4N4 · AsF5 ( 24 ) in a hitherto unknown modification. Possible reactions of the terminal SN groups are discussed and the structures of 11 and 24 are reported.  相似文献   

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