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1.
3-Methyl-3H-pyrazolo[1,5-d]tetrazoles 2 and 3-methyl-6-phenyl-3H-1,2,4-triazolo[1,5-d]tetrazole (4) have been unequivocally synthesized by annulation of the tetrazole moiety to the pyrazole resp. 1,2,4-triazole system. The constitution of some N-methyl substituted azolotetrazoles, formerly described as 3-methyl-3H-pyrazolo[1,5-d]tetrazoles 2, 3-methyl-6-phenyl-3H-1,2,4-triazolo[1,5-d]tetrazole (4) and 1-methyl-6-phenyl-1H-1,2,4-triazolo[4,3-d]tetrazole (5), has to be revised in favour of the corresponding mesoionic 2-methyl derivatives 2′, 4′, 5′. The structures of 3-methyl-3H- as well as of 2-methyl-2H-pyrazolo[1,5-d]tetrazole derivatives 2a, 2c, 2′a have been determined by X-ray analyses. The azapentalenic system is aromatic in all three measured compounds and mesoionic in the case of the 2-methyl-2H- substitution pattern. The phenyl and ester substituents are coplanar with the azapentalene system. 3-, 2-, and 1-Methylpyrazolo[1,5-d]tetrazoles exhibit different behaviour when allowed to react with stannous chloride or sodium ethoxide. Azolotetrazoles with a methyl substituent at N-1, N-2 or N-3 of the tetrazole moiety can be distinguished by a combination of 1H and 13C nmr with respect to the chemical shifts of the N-methyl group and the bridgehead carbon. Results of semiempirical calculations of the pyrazolo[1,5-d]tetrazole anion and of its N-methyl derivatives are discussed.  相似文献   

2.
1-Hydroxy-2-methyl-2-(penta-2,4-dienyl)-1,2-dihydronaphthalene ( 2 ), on treatment with 0,75N H2SO4 in ether at 0°, underwent a [1s, 2s]-sigmatropic rearrangement to give 2-methyl-1-(penta-2,4-dienyl)-naphthalene ( 5 ), cf. scheme 2. 2-Hydroxy-1-methyl-1-(penta-2,4-dienyl)-1,2-dihydronaphthalene ( 4 ) under the same conditions gave 38% of the [1s, 2s]-product 1-methyl-2-(penta-2,4-dienyl)-naphthalene ( 6 ), together with 26% 1-methylnaphthalene, 21% 1-methyl-4-(penta-2,4-dienyl)-naphthalene ( 7 ) and 1% 1-methyl-5-(penta-2,4-dienyl)-naphthalene ( 8 ), cf. scheme 2. Most likely the latter two naphthalene derivatives at least are products of an intermolecular process.  相似文献   

3.
The reaction of barbituric acid and its N-substituted derivatives and 2-thio analogs with cotarnine forms 5-(4-methoxy-6-methyl-5,6,7,8-tetrahydro-2H-1,3-methylenedioxy-[4,5-g]isoquinolinyl-1)barbituric acids, a new class of zwitter-ions, the structure of which was studied by 1 H and 13 C NMR spectroscopy and mass spectrometry. The prepared compounds exist in solution as stable intermolecular associates and have a complicated H-bonded structure.  相似文献   

4.
The diastereoisomeric (+)-[1,8-14C]-(1'R,6R, S)-α-bisabolol ( 2a ) and (?)-[1,8-14C]-(1′S, 6R, S)-α-bisabolol ( 2b ) were synthesized by reaction of the Grignard compound of [1,6-14C]-5-bromo-2-methyl-2-pentene ( 12 ) with (+)-(R)- and (?)-(S)-4-acetyl-1-methyl-1-cyclohexene, ( 6a ) and ( 6b ) respectively. For the preparation of compound 12, cyclopropyl methyl ketone was treated with [14C]-methyl magnesium iodide to form the carbinol 11, which was cleaved by HBr. Compounds 6a and 6b were synthesized from (+)-(R)- and (?)-(S)-limonene, ( 4a ) and ( 4b ), via the derivatives 5a , 6a and 5b , 6b respectively. - This synthesis established the absolute configuration at C(1′) of the natural α-bisabolols: (R) for (+)-α-bisabolol and (S) for (?)-α-bisabolol. - Feeding experiments with cultures of Myrothecium roridum and radioactive (+)-(1′R, 6R, S)- and (?)-(1′S, 6R, S)-α-bisabolol ( 2a ) and ( 2b ) gave negative results. These findings indicate that bisabolane derivatives are not intermediates in the biosynthesis of verrucarol (3).  相似文献   

5.
Reaction of 2-(3-hydroxy-3-methyl-1-butynyl)adamantan-2-ol with acetonitrile under Ritter reaction conditions is accompanied by isomerization and partial hydration where the water addition to the triple bond occurs nonselectively. As a result of reaction carried out in the presence of 8 equiv of sulfuric acid a mixture was obtained of N 2-[4-(1-acetylamino-2-adamantyl)-2-methyl-3-butyn-2-yl]acetamide, N 3-[1-(1-acetylamino-2-adamantyl)-3-methyl-2-oxo-3-butyl]-acetamide, and N 3-[1-(1-acetylamino-2-adamantyl)-3-methyl-1-oxo-3-butyl]acetamide in ~10:3:2 ratio. In the presence of 2 equiv of the acid the mixture obtained consisted of N 2-[4-(1-acetylamino-2-adamantyl)-2-methyl-3-butyn-2-yl]acetamide, N 3-[1-(1-acetylamino-2-adamantyl)-3-methyl-2-oxo-3-butyl]acetamide, and 1-(1-acetylamino-2-adamantyl)-3-methyl-2-buten-1-one in the same ratio. In Rupe reaction conditions we obtained instead of the expected ,-unsaturated ketones a mixture of 1-(1-hydroxy-2-adamantyl)-3-hydroxy-3-methylbutan-1-one and 1-(1-hydroxy-2-adamantyl)-3-hydroxy-3-methylbutan-2-one in a 5:3 ratio.  相似文献   

6.
Three different types of dioxidomolybdenum(VI) complexes of 4-acetyl-3-methyl-1-phenyl-5-pyrazolone (Hmp, I )), 3-methyl-1-phenyl-4-propionyl-5-pyrazolone (Hpp, II ), 4-butyryl-3-methyl-1-phenyl-5-pyrazolone (Hbutp, III ), and 4-isobutyryl-3-methyl-1-phenyl-5-pyrazolone (isobutp, IV ) have been isolated and characterized by various spectroscopic (FT-IR, UV/Vis, 1H and 13C NMR) techniques, thermal analysis and single crystal X-ray analysis. These complexes adopt a distorted six-coordinate octahedral geometry where ligands act as bidentate, coordinating through the two O atoms. These complexes have been used as catalysts to explore a single pot multicomponent (benzaldehyde or its derivatives, urea/thiourea and ethyl acetoacetate/phenyl acetoacatate) Biginelli reaction producing biologically active 3,4-dihydropyrimidin-2-(1H)-one and 3,4-dihydropyrimidin-2-(1H)-thione based biomolecules under solvent-free conditions. Presence of H2O2 improves the yield of dihydropyrimidin-2-(1H)-one but it acts as poison for the later molecule. Epoxidation of internal and terminal alkenes mainly resulted in the formation of the corresponding epoxide. The catalytic oxidative bromination of thymol, a reaction facilitated by vanadium dependent haloperoxidases, resulted in the formation of three product namely 2-bromothymol, 4-bromothymol and 2,4-bromothymol. Other phenol derivatives have also been brominated effectively.  相似文献   

7.
The convenient preparation of 6-fomylpyrimidinedione derivatives and 2- and 3-formylpyridine are described. Thus, 5-bromo-1,3-dimethyl- ( 1a ), 5-bromo-3-methyl-1-(2-nitrooxyethyl)- ( 1b ), and 5-bromo-3-methyl-1-(3-nitrooxypropyl)-2,4(1H,3H)-pyrimidine-dione ( 1c ) were converted to the corresponding 6-formyl compounds 2a, 2b , and 2c , respectively, in excellent yields by the reaction with triethylamine and 1,4-diazabicyclo[2.2.2]octane. These 6-formylpyrimidinedione derivatives are key intermediates for the preparation of 6-carbon-carbon substituted compounds, which are expected to be potential antitumor and antiviral agents. Similarly, 2-(and 3-)formylpyridine ( 9a (and 9b )) were obtained by the reaction of 2-(and 3)nitrooxymethylpyridine ( 8a (and 8b )) with 1,4-diazabicyclo[2.2.2]octane.  相似文献   

8.
By reaction of 1,2-diaminobenzimidazole with 1,3-diketones, acetoacetic ester and its derivatives, we have synthesized substituted 1,2,4-triazepino[2,3-a]benzimidazole and 5H-1,2,4-triazepino[2,3-a]benzimidazol-4-one. By reaction of 5H-2-methyl-1,2,4-triazepino[2,3-a]benzimidazol-4-one with aromatic aldehydes or phenyldiazonium chloride, we have obtained 3-arylidene(phenylazo) derivatives of this compound, and by reaction with P2S5 we have obtained 5H-2-methyl-1,2,4-triazepino[2,3-a]benzimidazole-4-thione. We have shown that when reacted with ammonia, primary or secondary amines, the latter forms 4-amino-substituted 2-methyl-1,2,4-triazepino[2,3-a]benzimidazole.  相似文献   

9.
On the Fischer-Indole Reaction. II. Thermal and Acid Catalysed Indolization of 1′-Alkenyl-2′-methyl-2′-phenylacetohydrazides Seven different 1′-alkenyl-2′-methyl-2′-phenylacetohydrazides, 6a-g , have been prepared by treatment of the methylphenylhydrazones 7 of appropriate ketones and aldehydes with acetyl chloride in pyridine. At 170° 6a-g are transformed into the N-methylindoles 3a-g and acetamide in moderate yield. N-Methylaniline is the other major reaction product indicating that homolytic cleavage of the weak N, N-bond in 6 is a major primary reaction step. It is likely but not proven that the N-methylindoles 3 are formed in a reaction sequence initiated by an uncatalysed concerted [3, 3]-sigmatropic rearrangement. Upon treatment of 6 with 0.5N dichloroacetic acid in anhydrous acetonitrile at room temperature a quantitative conversion to 3 is observed, interpreted as proceeding by a charge induced [3, 3]-sigmatropic rearrangement of protonated 6 in the rate determining step. The ketone derivatives 6a-e (R1 = alkyl) react 40-1000 times faster with acid than the aldehyde derivatives 6f and 6g (R1 = H). This is rationalized as a consequence of the increased basicity of 6a-e relative to 6f and 6g caused by a steric effect.  相似文献   

10.
在离子液体中一步法合成吡唑[5,4-b]-γ-吡喃衍生物   总被引:1,自引:0,他引:1  
芳醛、丙二腈与4,5-二氢-3-甲基-5-氧代-1-苯基吡唑在离子液体[bmim][BF4]中反应, 合成了2-氨基-4-芳基-3-氰基-5-甲基-7-苯基吡唑[5,4-b]-γ-吡喃衍生物, 该法快速、高效, 是一种洁净的合成方法. 产物的结构通过红外光谱、核磁共振氢谱和元素分析进行表征.  相似文献   

11.
Preparation of styryl derivatives of 2-phenyl-imidazo [1, 2-a]pyridine 2-(p-Tolyl)-imidazo [1, 2-a]pyridines and 7-methyl-2-phenyl-imidazo [1,2-a]-pyridines can be converted, in dimethylformamide, on reaction with anils of aromatic aldehydes in the presence of potassium hydroxide or potassium t-butoxide, into the corresponding 2-(stilben-4-yl)- and 2-phenyl-7-styry1-imidazo [1, 2-a]-pyridines (‘Anil-Synthesis’). The 2-(p-tolyl)-imidazo [1,2-a]pyridines react far less readily than the 7-methyl-2-phenyl-imidazo[1,2-a]pyridines.  相似文献   

12.
The targeted synthesis of 2-(methylsulfanyl)-6-(furan-2-yl)-4(3H)-selenoxo -pyrimidine-5-carbonitrile failed due to the formation 1-methyl-2-methylsulfanyl-6-oxo -4-(furan-2-yl)-1,6-dihydropyrimidine-5-carbonitrile. A new series of 5,6,7,8-tetrahydro-1-benzo thieno[2,3-d]pyrimidine-4-yl substituted selanyl derivatives were prepared by the reaction of sodium diselenide with 4-chloro-5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidine followed by the reaction with chloroacetic acid derivatives such as ethyl chloroacetate, chloroacetamide or chloroacetonitrile. Hydrazinolysis of ethyl (5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidine- 4-ylselanyl)acetate with hydrazine hydrate gave the corresponding hydrazino derivative. The latter reacted with ethyl acetoacetate, acetylacetone, diethyl malonate, ethoxymethylenemalononitrile or ethyl 2-cyano-3-ethoxyacetate to afford 5-methyl-2-[2-(5,6,7,8-tetrahydro-1-benzothieno [2,3-d]pyrimidine-4-ylselanyl)acetyl]-2,4-dihydropyrazol-3-one, 1-(3,5-dimethylpyrazol-1-yl)-2- (5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidin-4-ylselanyl)ethanone, 1-[2-(5,6,7,8-tetrahydro -1-benzothieno[2,3-d]pyrimidine-4-ylselanyl)acetyl]-2,4-dihydropyrazolidine-3,5-dione and 5-Amino-1-[2-(5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidin-4-ylselanyl)acetyl]-1H-pyrazol -4-yl substituted carbonitrile or ethyl carboxylate, respectively. The structure of the novel compounds was confirmed by spectroscopic tools (IR, 1H NMR 13C NMR and mass spectra) and elemental analysis.  相似文献   

13.
El-Kafrawy  Soliman  Baker  Mohamed  El-Kady 《中国化学》1990,8(5):469-473
Condensation of methyl 7-methylcoumarin-4-acetate ( 2 ) with primary amines and with anthranilic acid gave 7-methyl-2-oxo-N-aryl-2H-[1]-benzopyran-4-acetamide ( 4a—d ) and (7), respectively. Compound 7 underwent cyclization to give 2-(7-methyl-2-oxo-2H-[1]-benzopyran-4-yl)-methyl-4H-3,1-benzoxazin-4-one ( 3 ). The reaction of 3 with aromatic amines gave the corresponding quinazolone derivatives 5 which tautomerises to the thermodynamically more stable isomer 6 , whereas its reaction with Grignard reagents and aromatic aldehydes gave 8a, 8b , and 9a, 9b , respectively.  相似文献   

14.
It is shown by use of14C-labeling that the ring contraction reaction of 2,2-dichloro-6-methyl-4H-1-thiochroman-3,4-dione (1) leads to elimination of C-2 as CO2. Formation of the 5-methyl-2,3-dihydrobenzo[b]thiophen-2,3-dione (2) is suggested to proceed via hydrolytic opening of the thiolactone-binding in1. recyclisation and subsequent oxidation by unreacted1.
Herrn emer. Univ. Prof. Dr.E. Ziegler zur Vollendung seines 70. Lebensjahres mit besten Wünschen gewidmet.  相似文献   

15.
Summary Acetylation of the indazolquinones1a (6-anilino-),b (6-p-toluidino-),c (6-N-methylanilino-),g (6- or 5-methylthio-), andk (benz[f]-) by heating with acetic anhydride yields the 2-acetylindazolquinones4a, b, c, g, andk. Reductive acetylation of the quinones1c, g, h/h 1(6/5-methyl),k and — for structure elucidation — their 1-N- (2c) and 2-N- (3c, 3e)-methyl derivatives with acetic anhydride, zink powder, and sodium acetate gives the 1-acetyl-(7c, g, h/h 1,k), resp. 1-methyl- (8c), and 2-methyl- (9c, e) diacetoxyindazoles. In case of1k, two diacetyl derivatives were isolated in addition to the already known triacetyl derivative7k, regardless of the conditions chosen. Acetylation of the intermediate product of the reaction from phenylthio-benzoquinone with diazomethane also yields a triacetyl-hydroquinone (7f). UV/Vis, IR, and1H NMR spectroscopy were used for structure determination. Comparison of the UV/Vis spectra of the acetyl derivatives4 with those of1, 2, 3, and of compounds7 with those of analog substituted indazols shows that the acetyl group is located in position 2 with compounds4 and in position 1 with compounds7. By means of1H NMR spectra the position of the acetyl group can be determined by the effect of the carbonyl group on the proton in position3.
  相似文献   

16.
Contributions to the Chemistry of Phosphorus. 223. Hexaisopropylicosaphosphane(6), P20i? Pr6 — Preparation and Structure Determination of Two Constitutional Isomers by Nuclear Magnetic Resonance Hexaisopropyl-icosaphosphane(6) has been obtained by reaction of i-PrPCl2 with P4 and magnesium and subsequent thermolysis of the crude reaction product. The compound is formed as a mixture of two constitutional isomers 1 and 2 of equal abundance, which have been almost purely isolated by HPLC as a mixture of the diastereomers 1 a , 1 b and in the form of the separate configurational isomers 2 a and 2 b , respectively. According to NMR-spectroscopic investigations, the new conjuncto-phosphane skeletons of 1 and 2 consist of a P13(5)- and a P9(5)-structural element analogous to that of brexane and of two P11(5)-partial skeletons, respectively, joined in each case through a common P2-bridge. Thus, 1 is 6,7,9,16,17,20-hexaisopropyloctacyclo[10.8.0.02,14.03,11.04,8.05,10.013,18.015,19]icosaphosphane and 2 is 7,9,15,17,19,20-hexaisopropyl-octacyclo[14.2.1.15,8.02,14.03,12.04,10.06,11.013,18]icosaphosphane. The phosphorus hydrogen compound P20H6 [22, 2c] should exhibit the same constitutional isomerism.  相似文献   

17.
Novel tetracyclic ring systems viz. 3-methyl-1-oxo-12H-1, 2, 4-triazepino[3′,4′:3, 4][1, 2, 4]triazino[5, 6-b]indole ( 4a ) and 3-methyl-5-oxo-12H-1, 2, 4-triazepino[4′,3′:2, 3][1, 2, 4]triazino[5, 6-b]indole ( 5a ), having angular and linear structures respectively, were synthesized by the cyclization of 3-oxobutanoic acid [5H-1, 2, 4-triazino-[5, 6-b]indole-3-yl]hydrazone ( 3a ). However, cyclization of 3b (R = CHa, R1 = R2 = H) afforded the angular product 4b exclusively. Moreover, cyclization of 3c (R = R3 = H, R1 = F) yielded 7-fluoro-1-0xo-10H-1, 3-imidazo[2′,3′:3, 4][1, 2, 4]triazino[5, 6-b]indole ( 6c ) and 7-fluoro-3-oxo-10H-1, 3-imidazo[3′,2′:2, 3][1, 2, 4]triazino-[5, 6-b]indole ( 7c ) instead of the expected triazepinone derivatives. Compound 3d (R = R1 = H, R2 = CF3) also gave an imidazole derivative but only one angular product was obtained. In all these reactions, formation of the angular product involving cyclization at N-4 is favoured. Characterization of these products have been done by elemental analyses, ir, pmr, 19F nmr and mass spectral studies.  相似文献   

18.
In this study, we synthesized a new series of substituted aliphatic 1,3,4-thiadiazol-2(3H)-one derivatives (6-24) in yields ranging from 42 to 70% with an interesting mechanism that involves internal nucleophilic substitution followed by an SN2-type nucleophilic substitution. First, 1-(4-chlorophenyl)-2-((5-methyl-1,3,4-thiadiazol-2-yl)thio)ethanone (3) was synthesized from the reaction of 5-methyl-1,3,4-thiadiazole-2-thiol (1) with 2-bromo-1-(4-chlorophenyl)ethanone (2) in the presence of potassium hydroxide. Then, 1-(4-chlorophenyl)-2-((5-methyl-1,3,4-thiadiazol-2-yl)thio)ethanol (4) was synthesized by a reduction reaction of this compound using NaBH4. Finally, 5-methyl-3-alkyl-1,3,4-thiadiazol-2(3H)-one derivatives (6-24), which are the target compounds, were synthesized from the reaction of this compound (4), which is a secondary alcohol with various alkyl halides (5a-n) in the presence of sodium hydride (NaH). This study presents an interesting reaction mechanism related to the synthesis of aliphatic 1,3,4-thiadiazol-2(3H)-one derivatives that is not recorded in the literature.  相似文献   

19.
在不同反应条件下反应得到了两种1,2,3-三唑衍生物的配合物[Co(H2O)6][Co(L13]2·4H2O(1)和Cu(L222)(HL1=5-methyl-1-phenyl-1H-1,2,3-triazole-4-carboxylic acid;HL2=1-(4-iodophenyl)-5-methyl-1H-1,2,3-triazole-4-carboxylic acid)。通过X射线单晶衍射和红外光谱确定了晶体结构,同时对配合物12进行了表面作用分析(Hirshfeld surface analysis),在二维指纹图谱中可以清楚的看到配合物中的主要分子间作用。  相似文献   

20.
Isomerization of 2-allyl-6-methylaniline by the action of potassium hydroxide at 300°C afforded cis and trans isomers of 2-methyl-6-(1-propenyl)aniline which were converted into the corresponding carbamates by treatment with ethyl chloroformate. Ethyl 2-methyl-6-(1-propenyl)phenylcarbamates reacted with bromine to give mixtures of 4-(1-bromoethyl)-8-methyl-1,4-dihydro-2H-3,1-benzoxazin-2-one and ethyl 2- methyl-6-(1,2-dibromopropyl)phenylcarbamates. Treatment of the same compounds with N-bromosuccinimide resulted in formation of 2-ethoxy-4H-3,1-benzoxazine derivatives. The reaction of N-{6-methyl-2-[(Z)- 1-propenyl]-phenyl}methanesulfonamide gave a mixture of stereoisomeric N-[6-methyl-2- (1,2-dibromopropyl)-phenyl]-methanesulfonamides.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1815–1818.Original Russian Text Copyright © 2004 by Afonkin, Sotnikov, Gataullin, Spirikhin, Abdrakhmanov.For communication V, see [1].  相似文献   

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