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1.
Novel trisubstituted ethylenes, ring-substituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO2C4H9 (where R is 2-C6H5CH2O, 3-C6H5CH2O, 4-C6H5CH2O, 4-CH3COO, 3-CH3CO, 4-CH3CO, 4-CH3CONH, 2-CN, 3-CN, 4-CN, 4-(CH3)2N, 4-(C2H5)2N) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and butyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C-NMR. All the ethylenes were copolymerized with styrene (M1) in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r1) for the monomers is 4-C6H5CH2O (6.39) > 2-C6H5CH2O (2.06) > 3-CH3CO (1.86) > 3-C6H5CH2O (1.78) > 4-CH3COO (1.58) > 3-CN (1.47) > 4-CN (1.21) > 4-(C2H5)2N (1.19) > 4-(CH3)2N (1.18) > 2-CN (1.04) > 4-CH3CO (0.71) > 4-CH3CONH (0.63). Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (3.6–9.5% wt), which then decomposed in the 500–800°C range.  相似文献   

2.
The mass spectrometric investigation of specifically deuterium and 13C labelled 2-trimethylsilyl-l-phenoxyethanes proves that the dissociative ionization of β-silyl-substituted ethane derivatives (loss of PhO?; p-CH3C6H4O?; and C4H?9 from PhOCH2CH2SiMe3, p-MeC6H4OCH2CH2SiMe3 and CH3CH2CH(CH3)CH2-CH2SiMe3, respectively) yields the non-classical bridge ethylene trimethylsilanium ion and not the open-chain isomer. Other stable C5H13Si+? ions, characterised by collisional activation mass spectrometry, are the dimethyl n-propyl silicenium ion and the l-trimethylsilyl ethyl cation, both generated from the molecular ions of CH3CH2CH2Si(Cl)Me2 and CH3CH(Cl)SiMe3 via unimolecular loss of Cl?.  相似文献   

3.
Treatment of (CO)5WC[N(CH3)2]C6H4-p-CH3 (1) with lithium diisopropylamide (LDA) in THF at −78°C followed by quenching with D2O leads to incorporation of deuterium into the (E)-N-methyl group only. Reaction of the anion of 1 with benzyl bromide at −78°C followed by quenching with water gave the E-isomer of (CO)5WC[N(CH3)CH2CH2C6H5]C6H4-p-CH3 (2E, 26%) and recovered 1. When a mixture of the anion of 1 and benzyl bromide was warmed from −78°C to ambient temperature, a mixture of the E-isomer of the dibenzylated product (CO)5WC[N(CH3)CH(CH2C6H5)2]C6H4-p-CH was obtained. Reaction of the anion of 1 with allyl bromide gave (CO)5WC[N(CH3)CH2CH2CHCH2]C6H4-p-CH3 (5, 38%) and with methyl iodide gave a mixture of (CO)5WC[N(CH3)CH2CH3]C6H4-p-CH3 (6, 7%) and (CO)5W C[N(CH3)CH(CH3)2]C6H4-p-CH3 (7, 16%).  相似文献   

4.
η6-o-Chlorotoluene-η5-cyclopentadienyliron hexafluorophosphate undergoes nucleophilic substitution of the chlorine atom with anions generated (K2CO3/DMF) from methyl thioglycolate, diethyl malonate, dimethyl malonate, methyl acetoacetate and 2,4-pentanedione. The compounds prepared were o-CH3C6H4SCH2CO2CH3FeCp+PF6, o-CH3C6H4CH(CO2C2H5)2FeCp+PF6, o-CH3C6H4CH(CO2CH3)2FeCp+PF6, o-CH3C6H4CH(COCH3)CO2CH3FeCp+PF6 and o-CH3C6H4CH2COCH3FeCp+PF6 . Similarly, the reaction of diethyl malonate, dimethyl malonate, methyl acetoacetate anions and methylamine with η6-2,6-dichlorotoluene-η5-cyclopentadienyliron hexafluorophosphate yielded monosubstitution of one of the chloro groups. The complexes prepared in this study were η6-diethyl(3-chloro-2-methyl) phenylmalonate- η5-cyclopentadienyliron hexafluorophosphate, η6-dimethyl(3-chloro-2-methyl)phenylmalonate-η5-cyclopentadienyliron hexafluorophosphate, η6-methyl(3-chloro-2-methyl)phenylacetoacetate-η5-cyclopentadienyliron hexafluorophosphate and η6-3-chloro(2-methyl-N-methyl)aniline-η5-cyclopentadienyliron hexafluorophosphate. Reaction of η6-2,6-dichlorotoluene-η5-cyclopentadienyliron hexafluorophosphate with excess methanol as well as methyl thioglycolate in the presence of K2CO3 resulted in disubstitution of both chloro groups to yield new complexes, η6-2,6-dimethoxytoluene-η5-cyclopentadienyliron hexafluorophosphate and η6-methyl[(2-methylphenyl)1,3-dithio] diacetate-η55-cyclopentadienyliron hexafluorophosphate, respectively. Complexes o-CH3C6H4CH(CO2C2H5)2FeCp+PF6, o-CH3C6H4CH(CO2CH3)2FeCp+PF6 and o-CH3C6H4CH2 COCH3FeCp+ PF6 react with excess K2CO3 and benzyl bromide in refluxing methylene chloride to give 80–90% yields of complexes o-CH3C6H4C(CH2C6H5)(CO2C2H5)2FeCp+PF6, o-CH3C6H4C(CH2C6H5)(CO2CH3)2FeCp+PF6 and o-CH3C6H4CH(CH2C6H5)COCH3FeCp+PF6, respectively. Reaction of complex, o-CH3C6H4C(CH2C6H5)(CO2C2H5)2FeCp+PF6 with one molar equivalent of t-BuOK followed by acidic work-up gives o-(C2H5CO2CH2)C6H4CH(CO2C2H5)CH2C6H5FeCp+PF6. Similarly, reactions of complexes o-CH3C6H4C(CH2C6H5)(CO2C2H5)2FeCp+PF6 and o-CH3C6H4C(CH2C6H5)(CO2CH3)2FeCp+PF6 with t-BuOK in THF followed by alkylation with methyl iodide gave the new complexes, o-(C2H5O2C(CH3)CH)C6H4CH(CH2C6H5)CO2C2H5FeCp+PF6 and o-(CH3O2C(CH3)CH)C6H4CH(CH2C6H5)CO2CH3FeCp+PF6, respectively. Vacuum sublimation of the new complexes, o-CH3C6H4C(CH2C6H5)(CO2C2H5)2FeCp+PF6 and o-(C2H5O2CCH2)C6H4CH(CH2C6H5)CO2C2H5FeCp+PF6 gives o-CH3C6H4C(CH2C6H5)(CO2C2H5)2 and O-(C2H5O2CCH2)C6H4CH(CH2C6H5)CO2C2H5, respectively.  相似文献   

5.
Novel electrophilic trisubstituted ethylene monomers, oxy ring-disubstituted 2-cyano-3-phenyl-2-propenamides, RC6H3CH? C(CN)CONH2 (where R is 2,3-(CH3O)2, 2,4-(CH3O)2, 2,5-(CH3O)2, 2,6-(CH3O)2, 3,4-(CH3O)2, 3,5-(CH3O)2, 3-CH3?4-CH3O, 3-C2H5O-4-CH3O, 3,4-(C6H5CH2O)2, 2-C6H5CH2O-3-CH3O, 3-C6H5CH2O-4-CH3O, 4-C6H5CH2O-3-CH3O) were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and cyanoacetamide, and characterized by CHN analysis, IR, 1H- and 13C-NMR. Novel copolymers of the ethylenes and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator, AIBN at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H- and 13C-NMR. High Tg of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 300–500°C range with residue (2–9% wt), which then decomposed in the 500–800°C range.  相似文献   

6.
Novel trisubstituted ethylenes, ring-substituted propyl 2-cyano-3-phenyl-2-propenoates, RPhCH?C(CN)CO2C3H7 (where R is 2-C6H5CH2O, 3-C6H5CH2O, 4-C6H5CH2O, 4-CH3COO, 3-CH3CO, 4-CH3CONH, 2-CN, 3-CN, 4-CN, 4-(CH3)2N, 4-(C2H5)2N) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and propyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C-NMR. All the ethylenes were copolymerized with styrene (M1) in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H and 13C-NMR. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (2.7–8.6% wt.), which then decomposed in the 500–800°C range.  相似文献   

7.
The aggregation of two polymerisable surfactants dodecylethylmethacrylatedimethylammonium bromide (C12PS) and hexadecylethylmethacrylatedimethylammonium bromide (C16PS) was studied with a battery of methods. Both surfactants form premicelles at low concentration, and show a critical micelle concentration and a transition between spherical and rod-like micelles. The micelle ionization degree and the adsorption at the air/solution interface were also studied. Results are interpreted on the basis of the conformation of the polar head group.  相似文献   

8.
Density measurements were carried out for aqueous solutions of two cationic surfactants: dodecylethyldimethylammonium bromide (C12(EDMAB)) and benzyldimethyldodecylammonium bromide (BDDAB). On the basis of the obtained results of the measurements the CMC and partial molar volumes of the surfactants studied were also determined. The obtained CMC values were also analyzed with those accounted on the basis of the surface tension data from the previous paper [J. Harkot, B. Jańczuk, J. Colloid Interface Sci. (2008), submitted for publication]. The values of CMC determined from the surface tension and density measurements for C12(EDMAB) are equal to 9.9×10−3 and 1.5×10−2 M and for BDDAB to 5.25×10−3 and 5.3×10−3 M, respectively. These obtained values are very similar. However, in the literature it is difficult to find the CMC values for C12(EDMAB) and BDDAB determined by these two methods used by us—especially from the density measurements for BDDAB and surface tension measurements for C12(EDMAB). In the case of the apparent molar volumes of C12(EDMAB) there is a good agreement between the values obtained by us and those found in the literature. The CMC values for C12(EDMAB) and BDDAB were also determined on the basis of their surface tension and free energy of electrostatic interactions between the polar heads of these surfactants and compared with those obtained from the surface tension and density measurements. It was found that the theoretically obtained CMC values were close to those determined from the density and surface tension data for the C12(EDMAB) and that the ratios of the CMC values of the surfactants to their concentration at which the water surface tension decreased by about 20 mN/m proved that the presence of the aryl group in the BDDAB head instead of the methyl group caused that its micellization process was more inhibited in relation to its adsorption at air–water interface than that of C12(EDMAB).  相似文献   

9.
Radical telomerization of vinyl chloride with benzyl bromide and the competitive reaction of benzyl bromide with vinyl chloride and trimethylvinylsilane have been studied. The relative rate constant for the addition of C6H5C · H2 to vinyl chloride,k rel (with respect to trimethylvinylsilane), is close to unity, whereas the activation energy of the addition of C6H5C.H2 to vinyl chloride is considerably lower (by 7 kcal mol–1) than in the reaction involving trimethylvinylsilane. The possible fragmentation of the radical-adduct C6H5CH2CH2C.HCl was suggested as one of the possible reasons of underestimation ofk rel. The activation energy was estimated by the MPDO/3 method.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 886–888, May, 1993.  相似文献   

10.
Pyridine N-imine complexes of methylcobaloxime, CH3Co(Hdmg)2(R1— C5HnN+N?H) (n = 4; R1 = H, 2-CH3, 3-CH3, 4-CH3: n = 3; R1 = 2,6-CH3), have been synthesized by the reaction of CH3Co(Hdmg)2S(CH3)2 with a pyridine N-imine which is generated from a pyridine, hydroxylamine-O-sulfonic acid and K2CO3. The reactions of CH3Co(Hdmg)2(C5H5N+N?H) with acid anhydrides form new methylcobaloxime complexes with N-substituted pyridine N-imines, CH3Co(Hdmg)2(C5H5N+N?R2) R2 = COPh, COMe, COEt). With maleic anhydride, (pyridine N-acryloylimine)carboxylic acid is formed. With acetylenedicarboxylic acid dimethyl ester, 1,3-dipolar cycloaddition of the ligand gives pyrazolo[1,5-a]pyridine-2,3-dicarboxylic acid dimethyl ester.  相似文献   

11.
通过2-甲酰基吡啶与胺缩合制得Schiff碱,经NaBH4还原得到四个N-(2-吡啶甲基)芳胺(芳基=苯基,邻甲氧基苯基,对甲苯基及2-吡啶基),得到的芳胺及N-(2-吡啶乙基)甲胺与三甲基镓反应生成相应的N-(2-吡啶基)伯胺·二甲基合镓(Ⅲ)配合物。用元素分析、红外光谱、质子核磁共振、质谱等手段对配合物进行了结构鉴定和表征。  相似文献   

12.
The ionization potentials for the stereoisomers of trans-fused 1,2-dimethyl- and 1-ethyl-2-methyl-4-R-decahydroquinol-4-ols (R?C?CH, CH?CH2 or C2H5) and the appearance potentials for the [M–CH3]+ and [M–C2H5]+ ions (loss of 2-CH3 and 4-C2H5 groups potential, respectively) were measured by using the electron impact method. The ionization and appearance potential for [M–CH3]+ are always lower for the isomers with the axial 2-CH3 group. For the C-2 epimers, the difference between the appearance potentials for the [M–CH3]+ ion values is likely to be equal to the enthalpy differences between the ground states of the epimers and the dissociation energy differences between the axial and equatorial C2–CH3 bonds. The appearance potentials for [M–C2H5]+ for the C-4 epimers possessing the 4-C2H5 group were very similar. At the same time, the appearance potentials for the [M–CH3]+ ions were lower for less stable epimers which had an axial 4-C2H5 group.  相似文献   

13.
Abstract

The reaction of primary amine hydrochlorides with phosphorus oxychloride in the presence of 1/4 mole of H20 yields the title compounds I (R = C6H5-, 4-CH3CH6H4 ?′ 4-CH3CH6H4 ?, 3-CH3CH6H4 ? CF3CH2-). Hydrochlorides Of more basic amines do not yield any cyclic material. The compound I (R = C6H5) was isolated as one isomer. An X-ray crystallographic study has shown an open ring structure in which the two chlorine atoms are positioned on the same face of the P4N4 ring as the P-O-P bridge.  相似文献   

14.
The reaction of a series of β-methoxyvinyl trifluoromethyl ketones [CF3COC(R2)?C(OMe)R1, where R1 = Me, -(CH2)3-C3, -CH2)4-C3, Ph and R2 = H, Me, -(CH2)3-C4, -(CH2)4-C4] with N-methylhydroxylamine is reported. The regiochemistry of the reaction are explained by MO calculation data.  相似文献   

15.
Syntheses of titanatranes containing [(O-2,4-Me2C6H2-6-CH2)2-{O(CH2)nCH2}]N3− (n = 1,2) have been explored. Catalytic activity for ethylene polymerization by Ti2(OiPr)2{[(O-2,4-Me2C6H2-6-CH2)22-OCH2-CH2)]N}2 ( 1a ) - MAO catalyst increased at high temperature; the activity also increased upon addition of AlMe3. Ti(O- 2,6-iPr2C6H3){[(O-2,4-Me2C6H2-6-CH2)2(OCH2CH2)]N} ( 1c ) showed higher activity than 1a under the same conditions. Ti{[(O-2,4-Me2C6H2-6-CH2)2(HOCH2CH2CH2)]N}2 was isolated from the reaction of Ti(OiPr)4 with bis(2-hydroxy-3,5-dimethylbenzyl)-propanolamine; the structure was determined by X-ray crystallography.  相似文献   

16.
The synthesis and characterisation of the complexes [(p-CH3C6H4NCH(C6H3Y))Pd(OAc)]2 (II) are reported. These complexes react at very different rates with carbon monoxide in methanol to give the ortho-substituted esters, p-CH3C6H4NCHC6H3Y - 2R, R = CO2CH3, with electron withdrawing Y substituents slowing the reaction. The 13C{1H} data for II show a linear correlation of δ(C(2)) in the 5′-complexes (Y trans to PdC) with δ(C(4)) of monosubstituted benzene compounds. For Y = 5′-NO2, 4′-NO2 and 4′-Cl, the bis complex [{p-CH3C6H4NCH(
is formed in a secondary reaction.  相似文献   

17.
《Comptes Rendus Chimie》2003,6(4):485-491
Reactivity of 5-thioxylopyranosyl bromide and 1,5-dithioxylopyranoside towards thiolate anions. Reactivity of thiolate anion RS 2′ (C6H5–S) and 3′ (p-CH3–C6H4–S) towards 5-thioxylopyranosyl bromide Xyl–Br yields to the corresponding 1,5-dithioxylopyranoside Xyl–SR 7 R = C6H5– and 8 R = p-CH3–C6H4, respectively. In the presence of 4′ (C6H5–CH2–S) or 5′ (CH3–S), the reaction gives the 5-thioxylopyranose 9. Anions 5′ and 4′ react with 1,5-dithioxylopyranoside 10 Xyl–SR′ (R′ = –C6H4–CO–C6H4–CN) to give sulphide derivative 11 (CH3–S–C6H4–CO–C6H4– CN) and 13 (C6H5–CH2–S–C6H4–CO–C6H4–CN), respectively, and the 1,5–dithioxylose 12. These differences in terms of reactivity could be explained by the nucleophilic behaviour of the formed thiolate anion. To cite this article: D. Brevet et al., C. R. Chimie 6 (2003).  相似文献   

18.
Abstract

Thirty compounds of the type (ZC6H4)3PM(CO)5 where Z is 3-CH3, 4-CH3, 3-CH3O, 4-CH3O, 3-CF3, 4-CF3, 4-Cl, 4-F, 4-CH3S, or 4-(CH3) C and M is Cr, Mo, or W are reported, in addition to [4-(CH3)3SiC6H4]3 PW(CO)5 and [(2-CH3C6H4)n(C6H5)3–n P] M(CO)5 where n is 1 or 2 and M is Cr, Mo, or W. Phosphorus-31 NMR and infrared data are presented. In general, the compounds containing the more effective electron withdrawing substituents on the tertiary arylphosphines exhibit the larger 31P coordination chemical shifts, the higher carbonyl stretching frequencies, and the larger phosphorus-31-tungsten-183 coupling constants.  相似文献   

19.
New disiloxanes containing aromatic or aliphatic fluorinated groups are prepared and identified. The general formula of these compounds is: RF-Q-CH2-CH2-Si(CH3)2-O-Si(CH3)2-CH2-CH2-Q′-R′F · RF and R′F are halogenated groups such as C6F5-, CnF2n+1-, Cl(CFCl-CF2)n, CF3-CFH-CF2-, CF3-, or CCl3-. In most cases, Q or Q′ is an oxygen atom. Symmetrical disiloxanes are obtained by hydrolysis of corresponding fluorinated monochlorodimethylsilanes, and the asymmetrical ones are prepared in two steps by reacting the fluorinated olefins H2C = CH-Q-RF and H2C = CH-Q′-R′F with dihydrotetramethylsiloxane. The structures of these various compounds are elucidated by 1H-, 13C- NMR and IR spectroscopy  相似文献   

20.
Zusammenfassung Die Umsetzung von Alkalidiphenylphosphid mit Methylaryl-sulfonaten zu tert. Phosphinen gelingt umso leichter, je weniger Methylgruppen der Arylrest enthält. Folgende Phosphine (C6H5)2PR wurden dargestellt: R=2-CH3C6H4–, 4-CH3C6H4–, 2,4-(CH3)2C6H3– und 4-Methyl--naphthyl. Ebenso wurden die Phosphine mit R=3-(CH3)2NC6H4– und 2-(CH3)2NC6H4– aus den Dimethylanilinsulfonaten erhalten. Die Umsetzung von (C6H5)2PK mit Na-1,4-Chlorbenzolsulfonat im Molverhältnis 2:1 gibt fast quantitativ 1,4-Phenylen-bis-diphenylphosphin, im Molverhältnis 1:1 aber entsteht (bei tieferen Temperaturen) Diphenylphosphin-p-benzolsulfonat. Diphenyl-(2,4,6-trimethyl-phenyl)phosphin wird am besten aus Diphenylchlorphosphin und Mesitylmagnesiumbromid hergestellt.Zusammenfassung Alkali diphenylphosphides react with methylarylsulfonates giving tert. phosphines. The yield increases with decreasing number of methyl groups in the arylsulfonate. The following phosphines (C6H5)2PR were prepared: R=2-CH3C6H4, 4-CH3C6H4, 2,4-(CH3)2C6H3, and 4-methyl--naphthyl. Similarly the phosphines with R=3-(CH3)2NC6H4 and 2-(CH3)2NC6H4 were prepared from dimethylaniline sulfonates. The reaction of (C6H5)2PK with sodium 1,4 chlorophenyl sulfonate at a molar ratio of 2:1 yields nearly quantitatively 1,4-phenylene-bis(diphenylphosphine); however at a mole ratio of 1:1 and at lower temperatures sodium diphenylphosphine-p-phenyl sulfonate is obtained. The best way to prepare diphenyl(2,4,6-trimethyl-phenyl)phosphine was to use diphenyl-chloro phosphine and mesitylmagnesium bromide.  相似文献   

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