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1.
N-Benzylmorpholine,-piperidine, and-pyrrolidine ( 1A-C, resp.) are oxidised by RuO 4 (generated in situ) at both endocyclic and exocyclic (benzylic) N—α-methylene positions to afford lactams (and dioxo-derivatives) and benzaldehyde (and benzoyl derivatives), respectively.
The N-oxides of 1A-C, formed by a minor side reaction, are not involved as intermediates. Control experiments showed the transient formation of
endo- and exocyclic iminium cations trapped with NaCN as the corresponding nitriles. The proposed course of the RuO 4-mediated oxidation of 1A-C involves the consecutive steps 1⇒iminium cations+cyclic enamine⇒oxidation products. The endocyclic/exocyclic regioselectivity of the oxidation reaction lies
between 0.8 (for 1A) and 2.1 (for 1B). The amine cation radical and the N-α-C· carbon-centered radical seem not to be involved. 相似文献
2.
The synthesis and reactions of methyl 2-[3-(trifluoromethyl)phenyl]-4 H-furo[3,2- b]pyrrole-5-carboxylate ( 1a) are described. Upon reaction with methyl iodide, benzyl chloride, or acetic anhydride, this compound gave N-substituted products 1b-d. By hydrolysis of compounds 1a-c, the corresponding acids 2a-c were formed, or by reaction with hydrazine-hydrate, the corresponding carbohydrazides 3a-c were formed. By heating 2-[3-(trifluoromethyl)phenly]-4 H-furo[3,2- b]pyrrole-5-carboxylic acid ( 2a) in acetic anhydride, 4-acetyl-2-[3-(trifluoromethyl)phenyl]furo[3,2- b]pyrrole ( 4) was formed. By hydrolysis of 4, 2-[3-(trifluoromethyl)phenyl]-4 H-furo[3,2- b]pyrrole ( 5a) was formed, and reactions with methyl iodide or benzyl chloride gave N-substituted products 5b-c. The reaction of 4 with dimethyl butynedioate gave substituted benzo[ b]furan 6. Compound 3a reacted with triethyl orthoesters giving 7a-c, which afforded with phosphorus (V) sulphide the corresponding thiones 8a-c. The thiones 8a-c reacted with hydrazine hydrate to form hydrazine derivatives 9a-c. The reaction of triethyl orthoformiate with compounds 9a-c led to furo[2′,3′: 4,5]pyrrolo[1,2- d][1,2,4]triazolo[3,4- f][1,2,4]triazines 10a-c. Hydrazones 11a-c were formed from 3a-c and 5-[3-(trifluoromethyl)phenyl]furan-2-carboxaldehyde. The effect of microwave irradiation on some condensation reactions
was compared with “classical” conditions. The results showed that microwave irradiation shortens the reaction time while affording
comparable yields. 相似文献
3.
Reaction of 4-chloro-2-methyl-5-(1-methylhydrazino)-3(2 H)-pyridazinone ( 1 ) with carbon disulfide followed by alkylation yielded 2-alkylthio-4 H-pyridazino[4,5- e][1,3,4]thiadiazine derivatives 2 . Oxidative cyclization of 5-(4-substituted 1-methylthiosemicarbazido)-3(2 H)-pyridazinone derivatives 4 with N-bromosuccinimide also gave 2-substituted amino-4 H-pyridazino[4,5- e][1,3,4]thiadiazine derivatives 5 . Heating of 2 and 5 resulted in ring contraction to afford the corresponding pyrazolo[3,4- d]pyridazine derivatives 6, 7 via sulfur extrusion. A possible mechanism for the desulfurization reaction is discussed, comparing with a structural difference between a type of pyridazino[4,5- e][1,3,4]thiadiazine ( 2,5 ) and another one ( 9,11,13,15 ). 相似文献
4.
Summary. From extraction experiments and γ-activity measurements, the extraction constant corresponding to the equilibrium H +(aq) + 1
·Na +(nb) ⇆ 1
·H +(nb) + Na +(aq) taking place in the two-phase water-nitrobenzene system ( 1 = p-tert-butylcalix[4]arene-tetrakis( N, N-diethylacetamide); aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log K
ex(H +, 1
·Na +) = −1.4 ± 0.1. Further, the stability constant of the p-tert-butylcalix[4]arene-tetrakis( N, N-diethylacetamide)-H + complex in water saturated nitrobenzene was calculated for a temperature of 25°C as log β nb( 1
· H +) = 8.1 ± 0.1. 相似文献
5.
A modification of the method for the synthesis of N (1)-substituted derivatives of uracil is proposed using the Gilbert-Johnson reaction, which consists of the alkylation of 5-substituted
2,4-bis(trimethylsiloxy)pyrimidines with 1-bromo-2-(phenoxy)ethanes of low reactivity at 180-185° without solvent. The corresponding
1-[2-(phenoxy)ethyl]uracils, which were obtained in 55-74% yield, contained no impurities of the N (1), N (3)-disubstituted compounds.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, 1071–1075, July, 2005.
cf E. Ya. Lukevics and A. E. Zablotskaya. The Silyl Method for the Synthesis of Nucleosides [in Russian], Zinatne, Riga, 1985, 440 p. (Editor's note). 相似文献
6.
Reactions of TlCl 3 with picolinic acid (Hpic), nicotinic acid (Hnic), isonicotinic acid (Hinic) and 3-hydroxy-picolinic acid (H3hpic) afford
the isolation of new chlorothallium(III) complexes. The compounds are characterized by IR, Raman and multinuclear NMR ( 1H, 13C, 205Tl). The molecular structures of [TlCl 2(pic)(Hpic)]·0.5H 2O ( 1), [TlCl 2(nic)(Hnic)] ( 2), [TlCl(inic) 2]·0.6C 2H 5OH ( 3) and [TlCl(3hpic) 2(h3hpic)] ( 4) are determined by single-crystal X-ray diffraction. A distorted octahedral TlCl 2N 2O 2 core containing the O,N-chelating ligands is achieved in the monomeric complex 1. The coordination polyhedron in compounds 2–4 is pentagonal bipyramidal, i.e. TlCl 2NO 4 in 2, and TlClN 2O 4 in 3 and 4, respectively. O,O′,N-Bridging ligands result in a polymer chain for 2 and a three-dimensional polymeric association in 3, while compound 4 is monomeric ( O, N-and O,O-chelating ligands). 相似文献
7.
Abstract Selected 4-oxybenzaldehyde and 2,2-dioxybiphenyl cyclotriphosphazene derivatives were synthesized via substitution reactions through tailored control. The reactions of cyclotriphosphazene with 4-oxybenzaldehyde and 2,2-dioxybiphenyl gave the following synthesized derivatives: one mono-substituted open-chain compound, N 3P 3Cl 5(O 2C 7H 5) ( 1, 69%); mono spiro, N 3P 3Cl 4(O 2C1 2H 8) ( 2, 91.1%); non-gem tri-substituted, N 3P 3Cl 3 (O 6C 21H 15) ( 3, 17%); dispiro, N 3P 3Cl 2(O 4C 24H 16) ( 4, 92.3%); penta-substituted, N 3P 3Cl(O 10C 35H 25) (5, 92%);hexa-substituted, N 3P 3(O 12C 42H 30). Most of these derivatives ( 1–6) are obtained with good yield (up to 97%), This work provides a simple and available approach to obtain versatile cyclotriphosphazene derivatives, which is expected to further promote the use of HCCP as phosphorus platform for the construction of multi-functional materials. 相似文献
8.
11 and 12 molar reactions of dioxouranium(VI) acetate dihydrate with the monobasic bidentate Schiff bases, o-HOC 6H 4CH=N R or o-HOC 10H 6CH=N R ( R=C 2H 5, n-C 3H 7, n-C 4H 9 or C 6H 5) and bibasic tridentate Schiff bases, o-HOC 6H 4CH=N R(OH) or o-HOC 10H 6CH=N R(OH) ( R=–CH 2CH(CH 3)- or —CH 2CH 2CH 2–) have been studied and derivates of the type UO 2(O Ac) 2( SBH), UO 2(O Ac) 2( SBH) 2, UO 2(O Ac) 2( SBH
2) and UO 2(O Ac) 2( SBH
2) 2 (where SBH and SBH
2 represent monobasic bidentate and bibasic tridentate Schiff base molecules respectively) have been isolated. These have been characterized by elemental analysis, conductance measurements and IR spectral studies.
UO2
2+-Komplexe von Schiff-Basen. VII. Uranylacetat-Komplexe mit monobasischen zweizähnigen und bibasischen dreizähnigen Schiff-Basen
Zusammenfassung Es wurden in 1:1- und 1:2-molaren Reaktionen von UO2(OAc)2·2H2O mitSchiff-Basen (L) Komplexe des Typs UO2(OAc)2
L bzw. UO2(OAc)2
L
2 isoliert. Die Komplexe wurden mittels Elementaranalyse, Leitfähigkeitsmessungen und IR-Spektren untersucht. 相似文献
9.
Alkylation of homofullerene [6,6]‐C 60(CF 2) 2? dianion with the set of alkyl halides, RX, was established to demonstrate an effect of RX nature on the conversion, product composition, and regioselectivity. The respective C 60(CF 2) RH, C 60(CF 2) R2 and C 60(CF 2) R’ R’’ compounds were obtained in the reaction with sterically unhindered RX, isolated by HPLC and unequivocally characterized. The kinetic studies evidenced SN2 mechanism for both alkylation steps, yielding mono‐ and dialkylated C 60(CF 2), respectively, and indicated the negative charge localization at the bridgehead carbon atoms as well as a steric hindrance of the CF 2 moiety likely to be a key factors for the SN2 reaction mechanism and observed regioselectivity. The significant difference in the rate constants of the first and the second steps is attributed to the different activation barriers predicted by DFT calculations which makes possible to develop synthetic methods for the regioselective preparation of monoalkylated C 60(CF 2) RH and heterodialkylated C 60(CF 2) R’ R’’ derivatives. 相似文献
10.
Summary 3( Bis(alkylthio)methylene)-3 H-isobenzofuran-1-ones 2a–e and 2-( bis(alkylthio)methylene)-3(2 H)-benzofuranone derivatives 4a–c are obtained by reaction of phthalides 1a–d or 3(2 H)-benzofuranone (coumaranone 3), respectively, with carbon disulfide under basic conditions followed by alkylation. The reaction behaviour of the new compounds 2 and 4 is investigated. 2-((2-Dimethylthio-1-oxo)ethyl)benzoic acid N,N-dimethylamide ( 7a) and 2-((2-dimethylthio-1-oxo)ethyl)-benzoic acid 2-methylpiperidide ( 7b) are surprisingly formed instead of the methylthio substitution products by treatment of 2a with the corresponding amine in the presence of aluminum chloride. Herrn Professor Dr. Dr. h. c.Waldemar Adam zum 60. Geburtstag gewidmet 相似文献
11.
Oxo-bridged diiron(III) complexes [Fe2O(L1)2(H2O)2](ClO4)4 (1) and [Fe2O(L2)2(H2O)2](ClO4)4 (2), where L1 and L2 are tetradentate N-donor N,N′-bis(2-pyridylmethyl)-1,2-cyclohexanediamine and N,N′-bis(2-pyridylmethyl)ethane-1,2-diamine respectively, have been isolated as synthetic models of non-heme iron oxygenases and characterized by physicochemical and spectroscopic methods. Both the complexes have been studied as catalysts for the oxyfunctionalization of saturated hydrocarbons using green hydrogen peroxide (H2O2) as oxidant under mild conditions. The selectivity (A/K) and regioselectivity (3°/2°) in oxidative C–H functionalization of alkanes suggests the involvement of metal-based intermediate in the oxygenation reaction. The catalytic efficiency is found to be strongly dependent on the presence of acetic acid. Remarkable increase in conversion and selectivity favoring the formation of alcohols in the oxidation of cyclohexane and cyclooctane and exclusive hydroxylation of adamantane with drastic enhancement of regioselectivity has been achieved by the addition of acetic acid in the presence of H2O2. 相似文献
12.
Addition of amines to dibenzylidene sulfamide 1 a yields the corresponding Schiff bases 3 a, b and monobenzylidene sulfamide 2. Reaction of several dibenzylidene sulfamides 1 with various lithium-amides gives N 1-substituted N 2-benzylsulfamoyl-benzamidines 7 a-k
via an intramolecular hydride transfer reaction, whereas by treatment of 1 a with sodium amide 2-benzyl-3,5-diphenyl-3,4-dihydro-2 H-1,2,4,6-thiatriazine- 1,1-dioxide 8 is obtained, which on hydrolysis yields 9 and 11. Alkylation products are described, the isomeric products 12a/13a and 12b/13b are isolated, their structures are confirmed by synthesis, IR and NMR-spectra. 相似文献
13.
The reaction between di-2-pyridyl ketone thiosemicarbazone (dpktsc) and PdCl 2(CH 3CN) 2, generated in situ from the reaction between PdCl 2 and CH 3CN, gave the unprecedented [Pd 2Cl 3(κ 5-N py,N im,S,N py,N am-dpktsc-H)]·2CH 3CN ( 1) complex (py = pyridine, im = imine and am = amide). The identity of 1 was confirmed via its elemental analysis and spectroscopic properties. Infrared and 1H-NMR spectra confirmed the coordination of (dpktsc-H) ? to the palladium ions. The electronic absorption spectra measured in dmso and dmf and density functional theory (DFT) calculations revealed metal-to-ligand charge-transfer (MLCT), d–d and intra-ligand charge-transfer (ILCT) electronic transitions. X-ray structural analysis on a crystal of [Pd 2Cl 3(κ 5-N py,N im,S,N py,N am-dpktsc-H)]·H 2O ( 2) grown from dmf solution of 1 confirmed its formulation and showed the solid-state structure contains a web of molecules locked via a network of non-covalent interactions. Electrochemical measurements on 1 in dmf revealed metal- and ligand-based redox processes. In contrast to the electrochemical decomposition of uncoordinated dpktsc, coordinated (dpktsc-H) ? in 1 does not undergo electrochemical decomposition. Electrochemical titrations of 1 with p-toluenesulfonic acid monohydrate ( p-TSOH) revealed electro-catalytic proton reduction. Over-potential ( η) of 180 mV for the H 2 evolution was observed and is comparable to several molecular electro-catalysts for proton reduction. Controlled-potential electrolysis confirmed the electro-catalytic proton reduction by the Pd-complex. Electrochemical reactions of CO 2 in the presence of 1 exhibited a proton dependence, and metal- and ligand-based electrochemical reaction. 相似文献
14.
合成和表征了5个螺旋配位聚合物{[Cu(Hbpma)(H 2O) 4] 2(SO 4) 3·3.5H 2O} n ( 1)、{[Ni(Hbpma)(H 2O) 4] 4(SO 4) 6·10.75H 2O} n ( 2)、{[Mn(Hbpma)(H 2O) 4](SO 4) 1.5·3H 2O} n ( 3)、{[Zn(Hbpma)(H 2O) 4] 4(SO 4) 6·4H 2O·4CH 3OH}n ( 4)和{[Cu(Hbpma)2(H 2O) 2](SO 4) 2·9H 2O} n ( 5), 其中bpma代表 N, N'-双(3-吡啶甲基)胺。晶体结构分析表明配合物 1~ 4为一维链状结构, 配合物 5为二维层状结构, 其中金属离子由质子化的bpma配体桥连。值得注意的是, 采取反-反式构象的柔性bpma配体使得配合物 1和 2为假螺旋链结构, 配合物 3和 4为螺旋链结构, 配合物 5为螺旋层结构。同时研究了配合物的磁性和热稳定性。 相似文献
15.
The reactions of substituted furo[3,2- b]pyrrole-5-carboxhydrazides 1 with 5-arylfuran-2-carboxaldehydes 2, 4,5-disubstituted furan-2-carboxaldehydes 3 and thiophene- 2-carboxaldehyde 4 has been studied. The advantage of microwave irradiation on some of these reactions was reflected in the reduced reaction
time and increased yields. Reactions of 1 with 4-substituted 1,3-oxazol-5(4 H)-ones 11 led to diacylhydrazines 13 or to imidazole derivatives 14 depending on the temperature. 1,2,4-Triazole-3-thione 17 was synthesized by two-step reaction of 1 with phenylisothiocyanate and subsequent base-catalyzed cyclization of thiosemicarbazide 16. The effects of hydrazones 5–10 on inhibition of photosynthetic electron transport in spinach chloroplasts and chlorophyll content in the antialgal suspensions
of Chlorella vulgaris were investigated. 相似文献
16.
Abstract ( Z)-3-(3,4-diaryl-1,2,4-triazole-5-yl)prop-2-enoic acid derivatives were obtained in the course of the reaction of N
3-substituted amidrazones with maleic anhydride, and isomerized into the ( E) isomers by heating under reflux in acetic acid solution. The molecular structure of the compounds obtained was confirmed
by IR and 1H NMR spectroscopy, and by X-ray crystallography for (2 E)-3-(4,5-diphenyl-4 H-1,2,4-triazol-3-yl)prop-2-enoic acid. The antiviral and immunomodulating activity of several of the compounds was examined.
Graphical abstract
相似文献
17.
In the reaction with carbon disulfide, 2-amino-7-methyl-5-oxo-5 H-1,3,4-thiadiazolo[3,2- a]pyrimidine (1) forms the alkaline salts of substituted dithiocarbamic or iminodithiocarbonic acids depending on the molar ratio between 1, CS 2, and the alkali. The alkylation of these salts leads to the esters of N-(7-methyl-5-oxo-5 H-1,3,4-thiadiazolo[3,2- a]pyrimidine-2-yl)dithiocarbamic (2) and diesters of (7-methyl-5-oxo-5H-1,3,4-thiadiazolo[3,2- a]pyrimidine-2-yl)iminodithiocarbonic acids (3). The synthesis of asymmetric diesters 3 may be fulfilled based on monoesters 2.Translated from Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 14–14, August, 1994. 相似文献
18.
目的研究配体结构对NAMI-A衍生物水解机理、电化学性质的影响。方法制备了trans-[RuCl4(DMSO)(3-MePy)][(3-MePy)H](3-MePy=3-甲基吡啶,化合物1)和trans-[RuCl4(DMSO)(4-MePy)][(4-MePy)H](4-MePy=4-甲基吡啶,化合物2)。用UV、NMR、CV法研究化合物1、化合物2的水解机理-动力学、溶液稳定性及电化学性质。结果化合物1和化合物2与NAMI-A相似,在pH7.40的缓冲液中发生脱氯水解反应(Ⅰ氯水解及Ⅱ氯水解)(分步反应);在pH 5.00缓冲液中DMSO(二甲亚砜)及少量吡啶水解。测定各水解反应表观速率常数及半衰期、溶液稳定性及氧化还原电位。结论化合物1、化合物2的Ⅰ氯、Ⅱ氯及DMSO水解反应机理与NAMI-A相似,而且各水解速率与NAMI-A相差不大,即用甲基吡啶取代咪唑环,对NAMI-A衍生物的Ⅰ氯、Ⅱ氯及DMSO水解反应速率影响较小。化合物在酸性溶液中的稳定性明显高于中性溶液。 相似文献
19.
Two rare-earth metal coordination compounds, (NH 4) 4[Sm III2(Httha) 2]·16H 2O ( 1) (H 6ttha?=?triethylenetetramine- N,N,N′ ,N′′ ,N′′′ ,N′′′-hexaacetic acid) and (NH 4) 4[Sm III2(dtpa) 2]·10H 2O ( 2) (H 5dtpa?=?diethylenetriamine- N,N,N′ ,N′′ ,N′′-pentaacetic acid), have been synthesized through reflux and characterized by FT -IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction techniques. Sm III of (NH 4) 4[Sm III2(Httha) 2]·16H 2O ( 1) is nine-coordinate, forming tricapped trigonal prismatic coordination with three amine nitrogens and six oxygens, in which four oxygens are from one ttha and two from the other ttha. (NH 4) 4[Sm III2(Httha) 2]·16H 2O ( 1) crystallizes in the monoclinic crystal system with P2(1)/c space group. The crystal data are: a?=?13.9340(13) Å, b?=?22.890(3) Å, c?=?20.708(2) (14) Å, β?=?99.521(2)°, and V?=?6513.7(13) Å 3. There are two –NH +– groups in the [Sm III2(Httha) 2] 4?. The polymeric (NH 4) 4[Sm III2(dtpa) 2]·10H 2O ( 2) also is nine-coordinate with tricapped trigonal prismatic conformation and crystallizes in the triclinic crystal system with P–1 space group. The cell dimensions are: a?=?9.8240(8) Å, b?=?10.0329(9) Å, c?=?13.0941(11) Å, β?=?77.1640(10)°, and V?=?1227.30(18) Å 3. In (NH 4) 4[Sm III2(dtpa) 2]·10H 2O, there are two types of ammonium cations, which connect [Sm III2(dtpa) 2] 4? and lattice water through hydrogen bonds, leading to a 2-D ladder-like layer structure. 相似文献
20.
本文以对叔丁基杯[8]芳烃(H 8C 8A)为配体,在溶剂热条件下制得了3个3 d-5 f化合物,[Co 2Th 4(HC8A) 2O 2(OH) 2(DMF) 6]( 1)、[Ni 2Th 5(H 2C8A)(C 8A)O 4(OH) 2(DMF) 5(CH 3OH) 2]( 2)、[Zn 2Th 6(HC8A)(C8A)O 5(CH 3O)(C 3H 6NO 2) 2(DMF) 5(CH 3OH)]( 3)(其中H 8C8A=对叔丁基杯[8]芳烃,DMF=N,N-二甲基甲酰胺)。X-射线单晶测试表明,这3个化合物均为2个以尾对尾方式排列的杯[8]芳烃分子中间夹1个3 d-5 f核簇的三明治型结构。杯[8]芳烃均表现为双锥式构型,且每个锥式空腔下缘结合1个钍离子,双锥的连接处及2个杯芳烃分子之间由过渡金属离子或钍离子连接。不同过渡金属离子不同的配位环境导致3种不同核簇的形成。化合物 1的磁性研究表明,该化合物在低温下表现出弱铁磁性相互作用。 相似文献
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