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1.
The reaction of thioquinanthrene 1 with sodium alkoxides and α,ω-dihaloalkanes leads to the formation of α,ω-bis[4-(4-methoxy-3-quinolinylthio)-3-quinolinylthio]alkanes 4 . The yield depends on the nature of α,ω-dihalo-alkanes. The effect of α,ω-dihaloalkanes of the following types: XCH2X (X = Cl,Br,I), X(CH2)2X (X = Cl,Br,I), Br(CH2)3Br and Br(CH2)6Br were studied. The preparation of 4-alkoxy-3′-(ω-bromoalkylthio)-3,4′-diquinolinyl sulfide 3 and their transformation to α,ω-bis(4-alkoxy-3-quinolinylthio)alkanes 6 were studied as well.  相似文献   

2.
α ω-Alkane-bis-dimethylarsine Sulfides and Selenides, a Novel Class of Ligands The reaction of α,ω-alkane-bis-dimethylarsanes (CH3)2As? (CH2)n? As (CH3)2 with sulfur and selenium results in formation of the sulfides and selenides, respectively, (CH3)2As(X)? (CH2)n? As(CH3)2 or (CH3)2As(X)? (CH2)n? As(X)(CH3)2 (X = S, Se), which form chelat-complexes with the salts CoX2 · 6 H2O (X = Cl?, Br?, I?, NO3?). The UV-spectra of the complexes are presented and discussed.  相似文献   

3.
Three series of polyamides were prepared from diamines (hexamethylenediamine, bis-5-aminoamyl ether, p-xylylenediamine) and α,ω-oxaalkanedioic acids of formula HOOC(CH2)mO(CH2)nCOOH, where m = n = 3–10, in symmetric structures, but m = 3 or 4 in unsymmetric structures. The melting points of these polymers were plotted against the number of carbon atoms of the oxaalkylene groups. The melting points of polymers from each diamine fell on three different curves according to the structures of the dicarboxylic acids: symmetric ? (CH2)nO(CH2)n? ; unsymmetric ? (CH2)3O(CH2)n? , and unsymmetric ? (CH2)4O(CH2)n? . A minimum melting point is observed at about the same point of the acid structure in every curve of the unsymmetric dicarboxylic acids. The marked depression in the polymer melting points around the minimum point is attributed to the increase of the entropy of fusion.  相似文献   

4.
By means of AP measurements it has been shown that the stable [M? CH3]+ ions from α,ω-bis(trimethylsilyl) ethers of the type TMS? o? (CH2)n? O? TMS (n = 2 to 7) do not possess a cyclic structure.  相似文献   

5.
I.R. and Mass Spectroscopic Investigations on α,ω-Dihydrochloro Silanes H(SiCl2)nH with n = 3?7 Mass spectra of α,ω-dihydrochlorosilanes H(SiCl2)nH were analyzed respecting to their fragmentation. This shows, that the cleavage starts with the break of SiSi bonds, by preference in the middle of the chain. This is in accordance to the results of IR spectra which show very similar frequencies like perchlorooligo silanes. Thus, the lowest force constants of SiSi bondings in α,ω-dihydrochloro silanes, can be also expected in the middle of the chain.  相似文献   

6.
The isomerization and fragmentation of α,ω-dimethoxyalkyl ions a (CH3OCH2(CH2)n- CH+OCH3, n = 1-6) has been investigated by deuterium labelling. It is shown that a isomerizes to ion a' by hydride transfer from the ω-CH2 group to the positive charge at the α-C-atom before elimination of methanol. Both methoxy groups are lost as methanol. The amount of isomerization can be deduced from alkene elimination from [a ? CH3OH]+ ions in deuterated derivatives of a. On average at 70 eV three rearrangement steps involving hydride transfer are observed.  相似文献   

7.
Dinuclear Palladium(II), Platinum(II), and Iridium(III) Complexes of Bis[imidazol‐4‐yl]alkanes The reaction of bis(1,1′‐triphenylmethyl‐imidazol‐4‐yl) alkanes ((CH2)n bridged imidazoles L(CH2)nL, n = 3–6) with chloro bridged complexes [R3P(Cl)M(μ‐Cl)M(Cl)PR3] (M = Pd, Pt; R = Et, Pr, Bu) affords the dinuclear compounds [Cl2(R3P)M–L(CH2)nL–M(PR3)Cl2] 1 – 17 . The structures of [Cl2(Et3P)Pd–L(CH2)3L–Pd(PEt3)Cl2] ( 1 ), [Cl2(Bu3P)Pd–L(CH2)4L–Pd(PBu3)Cl2] ( 10 ), [Cl2(Et3P)Pd–L(CH2)5L–Pd(PEt3)Cl2] ( 3 ), [Cl2(Et3P)Pt–L(CH2)3L–Pt(PEt3)Cl2] ( 13 ) with trans Cl–M–Cl groups were determined by X‐ray diffraction. Similarly the complexes [Cl2(Cp*)Ir–L(CH2)nL–Ir(Cp*)Cl2] (n = 4–6) are obtained from [Cp*(Cl)Ir(μ‐Cl)2Ir(Cl)Cp*] and the methylene bridged bis(imidazoles).  相似文献   

8.
ω-Haloalkyltin trihalides, X(CH2)nSnX3 (n ≧ 3; X = halogen) can readily be prepared in high yields by the direct reaction of stannous halides with α,ω-dihaloalkanes, catalysed by trialkylantimony compounds. The compounds are versatile starting materials for the synthesis of a variety of ω-functionallysubstituted organotin compounds R3-mXmSn(CH2)n Y (R = alkyl, phenyl; m = 0-3; X = Cl, Br, O; Y = Br, NMe2, NEt2, COOH, CHOHR, R3Sn). 1H-NMR spectral data for a series of such compounds are presented. The trends observed in the chemical shifts and the 119Sn—methyl proton coupling constants of Me3-m BrmSn(CH2)nBr (m = 0-3; n = 3-5) are discussed in terms of inductive effects. Intramolecular coordination between the ω-bromine atom and tin could not be demonstrated.  相似文献   

9.
A new telechelic polyisobutylene diol, HO? CH2? PIB? CH2? OH, carrying two terminal primary hydroxyl end groups has been prepared from α,ω-di(isobutenyl)polyisobutylene, CH2?C(CH3)- CH2? PIB? CH2C(CH3)?CH2, by regioselective hydroboration followed by alkaline hydrogen peroxide oxidation. Infrared (IR) spectra, 1H-NMR analysis of the pure and silylated products, and ultraviolet (UV) spectra of phenylisocyanate-treated diols indicate quantitative yields and two ? CH2OH termini per polyisobutylene chain. The viscosity of HO? CH2? PIB? CH2? OH is higher than that of the starting α,ω-diolefin. The telechelic diol prepolymer opens new avenues to the synthesis of many new materials, e.g., polyurethanes.  相似文献   

10.
Unlike the α,ω-dihalogenopolydimethylsiloxanes, the α,ω-dichloropolydimethyl-N-methylsilazanes show a net preference for cyclic species with respect to linear structures at equilibrium. The aim of this study is to evaluate the perturbations in the molecular constitution of these α,ω-dihalogenopolydimethyl-N-methylsilazanes resulting from the substitution of the terminal chlorine atoms by fluorine atoms. This polymeric family was prepared by reacting (CH3)2SiF2 with nonamethylsilazane [(CH3)2SiNCH3]3. The redistribution of the fluorine atoms with the bridging methylimino groups reached an equilibrium after about 5 months' heating at 150°C for all the samples prepared. The relative abundance of the various molecular species and fragments at equilibrium was deduced from the quantitative analysis of the proton nuclear magnetic resonance (NMR) spectra. The molecular constitution at equilibrium is described by two constants. The first, K = [neso] [middles in chains]/[terminal moieties]2 = (2.8 ± 0.8) 10?2, shows that the presence of terminal fluorine atoms is unfavorable to the formation of short chains. On the other hand, the trimeric cyclic species [(CH3)2SiNCH3]3 are found to be highly favored (K°3 = 550 ± 100 mole/liter). These observations further confirm that the equilibrium constants which control the noncyclic part of polymeric families depend little on the functionality of the substituents exchanged [for example, on changing from ? N(CH3)2 to ? NCH3? ] when the reorganization heat order is one.  相似文献   

11.
Abstract

The synthesis, chemical and spectral properties of α-amino-ω-carboxyalkylphosphonic acids, (HO)2P(O)CH(NH2)(CH2) x CO2H, x = 2 to 6, and of α-amino-ω-carboxyalkyl-methylphosphinic acids CH3(HO)P(O)CH(NH2)(CH2) x CO2H, x = 2 to 6 are described and the fungicidal activity of some of these derivatives is reported.  相似文献   

12.
Electrochemical fluorination (ECF) of various heterocyclic compounds has been investigated. α,ω-Dimorpholinoalkanes of different chain length (n = 1-6) and of morpholinocyclohexene gave the perfluoro derivatives in yields up to 45%. The crystal and molecular structures of the perfluorinated compounds are presented. The mechanism of ECF for these compounds is discussed on the basis of a steric model. Perfluorocarbon emulsions of second generation were prepared by means of F-dimorpholines and F-cyclohexylmorpholine, acting both as oxygen carriers and as interfacial active compounds (IFACs). The stabilizing effect of these IFACs is interpreted. Semifluorinated alkanes, RfRh, are chemically inert and non-toxic. They are useful for blood substitutes in two ways: as co-surfactants to stabilize emulsions with perfluorocarbons and as oxygen carriers instead of perfluorocarbons. The high density of perfluorocarbons cause problems in some field of application in medicine. Therefore symmetrical diethers of the type RF(CH2)mO(CH2)nO(CH2)mRF were synthesized. These are inert and biocompatible compounds. Diethers with long RF-tail and long hydrocarbon spacer are ideal solubilizers for perfluorocarbons with hydrocarbons and vice versa. The diethers with short hydrocarbon spacer and long RF-tail can be applied in biological systems, because they are not soluble in lipid tissues. Perfluorocarbons (e. g. F-decalin, F-octane) are used as medical tools in ophthalmology, their purity is essential. Not totally fluorinated compounds (1 H-perfluoroalkanes, α,ω-dihydrogenoperfluoroalkanes) are characterized and discussed. 1H-perfluoroalkane is also formed by nucleophilic attack on perfluoroalkyl halide.  相似文献   

13.
Preparation and Characterization of α,ω-Dihydroperchloro Silanes Synthesis for the new compounds H(SiCl2)nH, n = 3?7 and HSi4Cl5 were described, starting from the perphenylated cyclosilanes. The new compounds were characterized and 1H- and 29Si-NMR spectra are discussed.  相似文献   

14.
The synthesis of a novel series of twelve 4‐(trihalomethyl)dipyrimidin‐2‐ylamines, from the cyclo‐condensation reaction of 4‐(trichloromethyl)‐2‐guanidinopyrimidine, with β‐alkoxyvinyl trihalomethyl ketones, of general formula: X3C‐C(O)‐C(R2)=C(R1)‐OR, where: X = F, Cl; R = Me, Et, ‐(CH2)2‐, ‐(CH2)3‐; R1 = H, Me; R2 = H, Me, ‐(CH2)2‐, ‐(CH2)3‐, is reported. The reactions were carried out in acetonitrile under reflux for 16 hours, leading to the dipyrimidin‐2‐ylamines in 65‐90% yield. Depending on the substituents of the vinyl ketone, tetrahydropyrimidines or aromatic pyrimidine rings were obtained from the cyclization reaction. When X = Cl, elimination of the trichloromethyl group was observed during the cyclization step. The structure of 4‐(trihalomethyl)dipyrimidin‐2‐ylamines was studied in detail by 1H‐, 13C‐ and 2D‐nmr spectroscopy.  相似文献   

15.
Synthesis of Fluoro-λ5-monophosphazenes and Fluoro-1,3-diaza-2λ5,4λ5-diphosphetidines by Means of the Staudinger Reaction 35 Tetrafluoro- and 2 difluorodiaza-diphosphetidines as well as 4 difluoro- and 30 monofluoro-λ5-monophosphazenes were prepared by the Staudinger reaction between tervalent phosphorus fluorides, RnPF3?n (n = 1, 2; R = R2N, (CH2)5N, O(CH2)4N, RO, (CH2O)2, alkyl, aryl) and phenylazides, X? C6H4N3 (X = H, 4-CH3, 4-Cl, 4-Br, 4-NO2, 3-NO2). PF3 does not react with phenylazide The influence of substituents on the structure of the reaction products is discussed. Kinetic measurements allowed to determine the constants λPI of the substituents (CH2)5N, O(CH2)4N and R(C6H5)N (R = CH3, C2H5, n-C4H9).  相似文献   

16.
Preparation of R4?nPb[Mn(CO)4P(C6H5)3]n Compounds (R?CH3, C6H5; n = 1, 2) As the first examples of organolead manganese carbonyls substituted in the manganese carbonyl ligand compounds of the type R4?nPb[Mn(CO)4P(C6H5)3]n (R?CH3, C6H5; n = 1, 2) have been prepared by the alkali salt method from R4?nPbCln and NaMn(CO)4P(C6H5)3. (C6H5)2Sn[Mn(CO)4P(C6H5)3]2 has been gained by the same method and also by thermal ligand exchange. According the IR data the ligand P(C6H5)3 is trans to the tetrahedrally surrounded lead. In solution to compounds are monomeric.  相似文献   

17.
Contribution to the mass spectrometry of substituted α,ω-alkane diamines The main mass spectral fragmentation pattern of compounds of types 1 to 4 is discussed. After loss of C6H5 · CH2 · from the molecular ion the acid correspondin to the N,N-disubstituted residue is splitted off. The mechanism of this fragmentation reaction depends on the member of CH2-groups between the two nitrogen atoms (Schemes 1 and 3) and on the substitution pattern of both nitrogens (Scheme 2).  相似文献   

18.
The reactions of 3,3′‐diaminobenzidine with 1,12‐dodecanediol in 1 : 1–1:3 molar ratios in the presence of RuCl2(PPh3)3 catalyst give poly(alkylenebenzimidazole), [ (CH2)11 O (CH2)11 Im / (CH2)10 Im ]n (Im: 5,5′‐dibenzimidazole‐2,2′‐diyl) (Ia‐Id) in 71–92% yields. The relative ratio between the [(CH2)11 O (CH2)11 Im ] unit (A) and the [‐ (CH2)10 Im ] unit (B) in the polymer chain varies depending on the ratio of the substrates used. The polymer Ia obtained from the 1 : 3 reaction contains these structural units in a 98 : 2 ratio. The polymers are soluble in polar solvents such as DMF (N,N‐dimethylformamide), DMSO (dimethyl sulfoxide), and NMP (N‐methyl‐2‐pyrrolidone) and have molecular weights Mn (Mw) of 4,200–4,800 (4,800–6,500) by GPC (polystyrene standard). The polymerization of the diol and 3,3′‐diaminobenzidine in higher molar ratios leads to partial cross‐linking of the resulting polymers Ie and If via condensation of imidazole NH group with CH2OH group. Similar reactions of 3,3′‐diaminobenzidine with α,ω‐diols, HO(CH2)mOH (m = 4–10), in a 1 : 3 molar ratio give the polymers containing [ (CH2)m−1 O (CH2) m−1 Im ] and [ (CH2) m−2 Im ] units with partial cross‐linked structures. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1383–1392, 1999  相似文献   

19.
20.
The homoserine and homomethionine sila analogs, (R)‐HOSi(Me2)CH2CH(NH2)CO2H ((R)‐ 21 ) and (R)‐MeSCH2Si(Me2)CH2CH(NH2)CO2H ((R)‐ 24 ), respectively, were each synthesized in nine steps and in 30 and 23% overall yield, respectively, from commercially available ClSiMe2CH2Cl. The key step of both syntheses was the asymmetric α‐bromination of an Evans amide to introduce the stereogenic center of the amino acids with defined absolute configuration. While the preparation of the homomethionine analog (R)‐ 24 followed the expected pathway, the sila analog of homoserine, (R)‐ 21 , was unexpectedly formed during the catalytic hydrogenation of an N3CH2‐substituted silane derivative.  相似文献   

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