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1.
On Chalcogenolates. 202. Derivatives of Selenodithioallophanic Acid. 1. Synthesis and Characterization of Selenodithioallophanates The hitherto not known, dark red colored selenodithioallophanate K[S2C? NH? CSe? NH2] has been prepared by reaction of K2[S2C?N? CN] with H2Se and characterized by means of electron absorption, infrared, and nuclear magnetic resonance spectra.  相似文献   

2.
On Chalcogenolates. 203. Derivatives of Selenodithioallophanic Acid. 2. Preparation and Properties of Alkyl Esters Synthesis and properties of selenodithioallophanic acid esters H2N? CSe? NH? CS? SR where R = CH3, C2H5 as well as their characterization by means of electron absorption, infrared, and nuclear magnetic resonance spectra are described.  相似文献   

3.
On Chalcogenolates. 204. Reaction of Acetamide with Carbon Disulfide. 1. Synthesis and Properties of N-Acetyl Dithiocarbamates Acetamide reacts with carbon disulfide in the presence of a strong base to form via the tetrabutyl ammonium salt the N-acetyl dithiocarbamates M[S2C? NH? CO? CH3] with M = Na, K, Rb, Cs, [N(nC4H9)4]. The new compounds have been characterized by means of electron absorption, infrared, nuclear magnetic resonance (1H and 13C), and mass spectra. Attempts to synthesize N-acetyl dithiocarbamic acid were not successful.  相似文献   

4.
On Chalcogenolates. 205. Reaction of Acetamide with Carbon Disulfide. 2. Esters of N-Acetyl Dithiocarbamic Acid The prepared yellow esters of N-acetyl dithiocarbamic acid H3C? CO? NH? CS? SR with R = CH3, C2H5 have been characterized by means of mass, electron absorption, infrared, and nuclear magnetic resonance spectra.  相似文献   

5.
On Chalcogenolates. 206. N-Thioacetyl Dithiocarbamates and Esters of N-Thioacetyl Dithiocarbamic Acid Thioacetamide reacts with carbon disulfide in the presence of KH to form via the tetrabutyl ammonium salt dark yellow N-thioacetyl dithiocarbamates M[S2C? NH? CS? CH3], where M = K, Rb, Cs. The salts as well as the methyl and ethyl ester have been characterized by means of electron absorption, infrared, nuclear magnetic resonance (1H and 13C), and mass spectra. Attempts to synthesize N-thioacetyl dithiocarbamic acid were not successful.  相似文献   

6.
Derivatives of Tricyanomethane 1. Synthesis, Characterization, and Decomposition of Chloro- and Bromotricyanomethane The title compounds X? C(CN)3, where X is Cl and Br, are characterized by means of electron absorption, nuclear magnetic resonance, vibrational, and mass spectra. The decompositions of the two compounds in solution have been studied kinetically at 5,0 ± 0,2 °C.  相似文献   

7.
The course of the reactions involved in the process of degradation of strychnine ( 1 ) to Wieland-Gumlich aldehyde (WGA) ( 2 ), first performed by Wieland, Kaziro & Gumlich , has been elucidated. 23-Isonitrosostrychnine hydrochloride ( 9a ) upon treatment with thionyl chloride undergoes a fragmentation (2nd order Beckmann rearrangement), thus furnishing N(a)-cyanoformyl-WGA hydrochloride ( 14a ). On heating in an acidic medium, the latter compound is transformed — at least partially via the cyclic urethane 15 — into WGA ( 2 ), which is an important keyintermediate in the syntheses of strychnine and curare alkaloids. The compound 2 can now be obtained in high purity and good yield. A corresponding degradation has been realized with quaternary analogues ( 27 → 3 ) as well as with 10-chlorostrychnine ( 58 → 62 ). 10-Chlorostrychnine ( 58 ) was prepared by chlorination of strychnine with chlorine in conc. hydrochloric acid according to Leuchs & Steinborn. As by-products of the reaction, 10, 15-dichlorostrychnine ( 59 ) and 10, 15, 19-trichlorostrychnine ( 60 ) could be identified. Starting from WGA a series of derivatives have been prepared. Special mention is made of the two epimeric methyl ethers 18 and 19 . The absolute configuration at the centre 17 of WGA and of these two substances has been established by optical comparisons of 3 epimeric pairs. The methyl ether 18 , by-product « B », is obtained if methanol is used in working up the Beckmann rearrangement products of 23-isonitrosostrychnine hydrochloride ( 9a ). A second by-product, « A », results by working up under alkaline conditions. This compound has the structure 44 with inverted configuration at centre 16. Degradation of 44 under controlled conditions leads either to WG-diol ( 42 ) or to 16-epi-WG-diol ( 51 ). Besides « A z.rdang; and « B » a series of by-products and intermediates ( 16, 17, 11a, 22. 23, 24 and 25 ) could be detected in the course of the process of strychnine degradation.  相似文献   

8.
On Chalcogenolates. 152. Studies on Derivatives of N-Thioformyl Dithiocarbamic Acid. 2. Crystal Structure of Tetra-n-butylammonium N-Thioformyl Dithiocarbamate The title compound [N(nC4H9)4][S2C? NH? CS? H] crystallizes with Z = 2 in the triclinic space group P1 with cell dimensions a = 9.694(2) Å, b = 11.478(3) Å, c = 12.551(6) Å, α = 63.03(3)°, β = 66.42(2)°, γ = 85.60(2)°. The crystal structure has been determined from single crystal X-ray data measured at 20°C and refined to a conventional R of 0.061 for 2249 independent reflections (Rw = 0.042). The structure is built up of dimeric aggregates consisting of 2[N(nC4H9)4]+ cations and 2[S2C? NH? CS? H]? anions. The two anions are linked together by ? CS? S…?H? N bridges. To make possible a space saving stacking of the dimeric aggregates in the crystal, one methyl group in terminal position of one n-butyl chain in the cation has gauche conformation.  相似文献   

9.
Synthesis and Properties of Diphthalocyaninates of Bismuth, [Bi(Pc)2]k (k = 1?, 0, 1+); Crystal Structure of mixed-valent [Bi(Pc)2] · CH2Cl2 Blue di(phthalocyaninato(2-))bismuthate(III), [Bi(Pc2?)2]?, is obtained by the reaction of BiO(NO3) with molten 1,2-dicyanobenzene in the presence of potassium methylate and isolated as tetra-n-butylammonium (nBu4N)+ and bis(triphenylphosphine)iminium (PNP)+ salt. Green mixed-valent [Bi(Pc)2] · CH2Cl2 is prepared by anodic oxidation of [Bi(Pc2?)2]?. It crystallizes in the orthorhombic γ modification (Pnma; a = 28.176(5), b = 22.913(3), c = 7.925(1) Å, Z = 4). The BiIII ion is eightfold coordinated by the Niso atoms of the slightly distorted Pc ligands in a square antiprismatic manner. The average Bi? Niso bond distance is 2.467 Å. The complex is paramagnetic (μeff = 1.84 μB). Oxidation of [Bi(Pc2?)2]? with bromine yields purple, diamagnetic [Bi(Pc?)2]Brx (1.5 ≤ x ≤ 2.5). The redox properties are investigated electrochemically. UV-Vis-NIR, MIR/FIR and resonance Raman spectra of the new bismuth(III) complexes are discussed and compared with those of diphthalocyaninates of the lanthanides.  相似文献   

10.
On Chalcogenolates. 151. Studies on Derivatives of N-Thioformyl Dithiocarbamic Acid. 1. Synthesis and Properties of N-Thioformyl Dithiocarbamates The N-thioformyl dithiocarbamates M[S2C? NH? CS? H], where M = K, Rb, Cs, Tl, NH4, [N(nC4H9)4], Na[S2C? NH? CS? H] · 0.5 H2O, and Ba[S2C? NH? CS? H]2 · 3 HO? CH2? CH2? OCH3 have been prepared by use of partial different procedures. The compounds were characterized with chemical and thermal methods as well as by means of electron absorption, infrared, nuclear magnetic resonance (1H and 13C), and mass spectra. Attempts to synthesize N-thioformyl dithiocarbamic acid were not successful.  相似文献   

11.
On Chalcogenolates. 96. Studies on Trimethylsilyl Carbonates of Alkali Metals The trimethylsilyl carbonates M[O2COSi(CH3)3] with M = Li, Na, K, Rb, Cs have been prepared by reaction of Co2 with the corresponding silanolate. Infrared spectra, electron absorption spectra, 1H-NMR spectra as well as mass spectra are communicated. In aqueous solution the equivalent conductivities of [O2COSi(CH3)3]? have been determined by means of conductivity measurements. The diffusion coefficient of the ion was calculated. The dissociation constant of trimethylsilyl carbonic acid in water at 20°C is Ka = (4,83 ± 0,5) · 10?10. The thermodynamic data of the dissociation were calculated.  相似文献   

12.
On the Preparation of Di(i-propyl)thiosulfonium Salts [1] The preparation of the mercaptosulfonium salts (i-C3H7)2SSX+SbCl6? (X = H, D) and of the chlorothiosulfonium salts (i-C3H7)2SSCl+MF6? (M = As, Sb) and (i-C3H7)2SSSCl+SbCl6? is reported. They are formed by reaction of chlorinated or protonated (i-C3H7)2S with excess H2S or SCl2 and S2Cl2. The thiosulfonium compounds are characterized by vibrational and NMR spectroscopic methods.  相似文献   

13.
On Chalcogenolates. 134. Studies on Esters of Haloformic Acids 2. Synthesis and Properties of Se-Alkyl Esters of Chloromonothiomonoselenoformic Acid The hitherto unknown esters RSe? CS? Cl with R ? C2H5 and nC3H7 have been prepared by reaction of thiophosgene with the corresponding alkane selenol. The compounds have been characterized with electron absorption, nuclear magnetic resonance (1H, 13C, and 77Se), infrared, and mass spectra.  相似文献   

14.
Studies on the Reactivity of Antimony Pentachloride. III. The Reaction of Antimony(V) Chloride and Methylisocyanate Methylisocyanate CH3NCO reacts with SbCl5 in boiling CCl4 by an insertion-reaction to a product of the formula C5H6Cl9N2O2Sb I, which has the chlorformamidinium-structure (Cl? C(O)? N(CH3)? CCl? N(CH3)? C(O)? Cl)⊕SbCl6?. Hydrolysis of I yields the heterocycle C5H6N2O4 II. The reaction with methanol gives (CH3? NH? CCl? NH? CH3)⊕SbCl6? III and (CH3? NH? CCl? N(CH3)? C(O)? OCH3)⊕SbCl6? IV. The i.r. and Raman spectra of the compounds I, III and IV are discussed.  相似文献   

15.
The reactivity of hydroxy-indoles under the conditions of the Mannich-reaction has been studied. The electrophilic side-chain enters in each case in a position ortho to the phenolic group. 4-Hydroxy-indole is substituted in the 5-, 5-hydroxy-indole in the 4-, 6-hydroxy-indole in the 7-, and 7-hydroxy-indole probably in the 6-position. The structures of the Mannich bases from 4-, 5- and 6-hydroxy-indole have been confirmed by comparison of the hydroxy-methyl-indoles obtained by reductive desamination with hydroxy-methyl-indoles prepared by unambiguous total synthesis.  相似文献   

16.
Synthesis and Spectroscopical Properties of Di(phthalocyaninato(1?))lanthanidepolybromide; Crystal Structure of α-Di(phthalocyaninato)samariumpolybromide, α-[Sm(Pc)2]Br1.45 and α-Di(phthalocyaninato)samariumperchlorate, α-[Sm(Pc)2](ClO4)0.63 Bronze-coloured di(phthalocyaninato)lanthanidepolybromide, [Ln(Pc?)2]Bry (Ln = La…(? Ce, Pm)…Lu; y > 1.5) is prepared by oxidation of (nBu4N)[Ln(Pc2?)2] with bromine in excess. The UV-VIS-NIR spectra show the typical B and Q1 bands of the Pc? ligand at ~ 14 kK and ~ 20 kK. For the [Ln(Pc?)2]+ cation a NIR(D) band between 9,14 kK (La) and 11,50 kK (Lu) is characteristic for dimeric cofacial Pc? radicals. Within the row La…Lu, there is a linear relationship of the hypsochromic shift of the strong bands and the LnIII radius. In the case of La? Nd the D band shifts successively with longer time of bromination to ~ 3 kK as a result of increasing electron delocalisation. Characteristic vibrational bands are at ~ 1350/1450 cm?1 (IR) and ~ 560/1120/1170/1600 cm?1 (RR). In the FT-Raman spectra the totally symmetric Ln? N stretching vibration between 141 cm?1 (La) and 172 cm?1 (Lu) is selectively enhanced. As shown by α-[Sm(Pc)2]Br1,45 and α-[Sm(Pc)2](ClO4)0,63 only partially ringoxidized complexes are obtained by the anodic oxidation. Both crystallize in the tetragonal space group P4/nnc. The [Sm(Pc)2] molecular building block contains two nearly planar staggered (~41°) Pc rings packed in columns parallel along [001] leading to the quasi-one-dimensional structure. There is a statistical disorder of the SmIII and the ClO4? resp. Br?/Br3? ions over two incompletely filled crystallographic positions for the cation resp. anion. This results in a partial oxidation of the Pc ligand, which in the picture of localized valence states for α-[Sm(Pc)2](ClO4)0,63 corresponds to [SmPc?Pc2?] · 2[Sm(Pc?)2](ClO4). Accepting the same valence state for [Sm(Pc)2]Br1,45 five positive charges are compensated by two Br? and three Br3?. The spectroscopic differences of the partially and fully oxidized complexes are discussed.  相似文献   

17.
18.
On Chalcogenolates. 197. Studies on Polythiocuprates(I) [Cu(Sx)]?. 1. Properties and Reactions of Ammonium Tetrathiocuprate(I) The properties of NH4[Cu(S4)] have been studied. In watery alkaline media it decomposes into CuS and S; in the presence of carbon disulfide CuS, Sx2?, and CS32? besides CS42? and S2CO2? are formed. The compound (NH4)2[Cu2CS7], described in literature, does not exist. In dimethylformamide dissolved NH4[Cu(S4)] decomposes via the radical anion S3?. NH4[Cu(S4)] reacts with n-butyl chloride to yield the substituted sulfanes (C4H9)2Sx with x = 1, 2, and 3.  相似文献   

19.
20.
The Syntheses and Vibrational Spectra of the Homoleptic Metal Acetonitrile Cations [Au(NCCH3)2]+, [Pd(NCCH3)4]2+, [Pt(NCCH3)4]2+, and the Adduct CH3CN · SbF5. The Crystal and Molecular Structures of [M(NCCH3)4][SbF6]2 · CH3CN, M = Pd or Pt Solvolyses of the homoleptic metal carbonyl salts [M(CO)4][Sb2F11]2, M = Pd or Pt, in acetonitrile leads at 50 °C both to complete ligand exchange for the cations as well as to a conversion of the di-octahedral anion [Sb2F11] into [SbF6] and the molecular adduct CH3CN · SbF5 according to: [M(CO)4][Sb2F11]2 + 7 CH3CN → [M(NCCH3)4][SbF6]2 · CH3CN + 2 CH3CN · SbF5 + 4 CO M = Pd, Pt The monosolvated [M(NCCH3)4][SbF6]2 · CH3CN are obtained as single crystals from solution and are structurally characterized by single crystal x-ray diffraction. Both salts are isostructural. The cations are square planar but the N–C–C-sceletial groups of the ligands depart slightly from linearity. The new acetonitrile complexes as well as [Au(NCCH3)2][SbF6] and the adduct CH3CN · SbF5 are completely characterized by vibrational spectroscopy.  相似文献   

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