首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
1-(Alkylthio)difluoropropynes regioselectively add dialkylamines and mercaptans with formation of 1-(alkylthio)-2-dialkylamino(alkylthio)ethenes, which exist only in the form of one (presumably the trans isomer) geometrical isomer. Thermal transformation of 1-(alkylthio)difluoropropynes occurs at a temperature of under 100°C and leads to the formation of 2,4-bis(polyfluoroalkyl)-3-(alkylthio)thiophenes. © 1998 John Wiley & Sons, Inc.Heteroatom Chem 9:151–154, 1998  相似文献   

2.
The reaction of 1-(triethylsilyl)aziridine with alkanethiols proceeds with splitting out of aziridine and the formation of (alkylthio)triethylsilanes. The reaction of 1-(triethylsilyl)aziridine with 2-mercaptoethanol leads to 2-(triethylsilyloxy)ethanethiol; the same reaction in a closed system leads to [2-(2-aminoethylthiol)ethoxy]triethylsilane. 1-[2-(Trialkylsilyl)ethyl]aziridines react with 2-mercaptoethanol and with mercapto carboyxlic acids with opening of the aziridine ring.See [1] for Communication 14.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 891–893, July, 1988.  相似文献   

3.
The title compounds, readily available from the S-alkylation of pyridinium 1-[alkylthio(thiocarbonyl)](ethoxycarbonylacetyl)methylides with alkyl halides or alkyl bromoacetates, were treated with a base and then a dehydrogenating agent to provide some unique products such as 3-[bis(alkylthio)methylene]-2(3H)-indolizinones and dialkyl 7-methyl-4-oxo-1,4,8,8a-tetrahydro-1,4-thiazino[3,4,5-cd]indolizine-1,5-dicarboxylates. On the other hand, similar reaction of these pyridinium salts in the absence of the dehydrogenating agent afforded alkyl 2-hydroxyindlizine-3-carboxythiolates, whose yields were increased by adding trifluoroacetic acid to the reaction mixture. The structures of some products were confirmed by the X-ray analyses.  相似文献   

4.
Starting from readily available ethyl-4-nitropyrrole-2-carboxylate ( 1 ), substituted 1-methyl-2-(1,3,4-thiadiazol-2-yl)-4-nitropyrroles and 1-methyl-2-(1,3,4-oxadiazol-2-yl)-4-nitropyrroles were prepared. The reaction of 1 with diazomethane gave ethyl 1-methyl-4-nitropyrrole-2-carboxylate ( 2 ). Reaction of compound 2 with hydrazine hydrate afforded the corresponding hydrazide 3 . The reaction of 3 with formic acid yielded 1-(1-methyl-4-nitropyrrole-2-carboxyl)-2-(formyl)hydrazine ( 7 ). Refluxing of the latter with phosphorus pentasulfide in xylene yielded compound 6 in 40% yield. Reaction of compound 7 with phosphorus pentoxide afforded compound 9 . Reaction of compound 3 with 1,1′-carboxyldiimidazole in the presence of triethylamine yielded 2-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-oxadiazoline-4(H)-5-one ( 11 ). Refluxing compound 3 with cyanogen bromide in methanol gave compound 12 . Compound 13 could be obtained through the reaction of compound 3 with carbon disulfide in basic medium. Alkylation of compound 13 afforded the correspanding alkylthio derivative 14 . Reaction of 1-methyl-4-nitropyrrole-2-carboxylic acid ( 15 ) with thiosemicarbazide and phosphorus oxychloride gave 2-amino-5-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-thiadiazole ( 16 ). Sandmeyer reaction of compound 16 yielded 2-chloro-5-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-thiadiazole ( 17 ). Refluxing of the latter with thiourea afforded 2-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-thiadiazoline-4(H)-5-thione ( 18 ). Alkylation of compound 18 gave the corresponding alkylthio derivative 19 . Oxidation of the latter with hydrogen peroxide in acetic acid yielded 2-(1-methyl-4-nitro-2-pyrrolyl)-5-methylsulfonyl-1,3,4-thiadiazole ( 20 ).  相似文献   

5.
A simple and efficient aerobic oxidative dehydrogenation reaction method for the conversion of 2-(alkylthio)-1,4-dihydropyrimidines to 2-(alkylthio)pyrimidines using copper catalyst with no additives, such as an oxidant, acid, or base, has been developed. The reaction was successful with a wide range of 2-(alkylthio)-1,4-dihydropyrimidine substrates.  相似文献   

6.
The base alkylation of 2,3-dimercapto-1-propanol with alkyl halides leads in good yield to 2,3-bis(alkylthio)-1-propanol and dialkyl sulfide. The reaction of 2,3-bis(alkylthio)-1-propanol with catalytic concentrated sulfuric acid proceeds with rearrangement to give 1,2,3-tris(alkylthio)propane and dialkyl disulfide. The rearrangement reaction takes place through a common intermediate thiaranium intermediate 8.  相似文献   

7.
The preparation of 1,4-dihydro-4-oxo-3′-alkylthio-3,4′-diquinolinyl sulfides 3 or 1,4-dihydro-4-oxo-3-(alkylthio)quinolines 4 by acid catalysed hydrolysis of 4-methoxy-3′-alkylthio-3,4′-diquinolinyl sulfides 1 or 4-methoxy-3-(alkylthio)-quinolines 2 is described. The reactions of 4-methoxy-3′-alkylthio-3,4′-diquinolinyl sulfides 1 or 1,4-dihydro-4-oxo-3′-alkylthio-3,4′-diquinolinyl sulfides 3 with phosphoryl chloride in DMF afforded 4-chloro-3′-alkylthio-3,4′-diquinolinyl sulfides 5 . Treatment of the title compounds 1 or 3 with boiling phosphoryl chloride systems:leads to 4-chloro-3-(alkylthio)quinolines 6 and thioquinanthrene but those of alkoxy- or oxo-quinolines 2 or 4 lead to 4-chloro-3-(alkylthio)quinolines 6 . The reactions of N-methyl-4(1H)-quinolinones 3n and 4n with phosphoryl chloride directed to 4-chloro-3-(alkylthio)quinolines 6 were studied as well.  相似文献   

8.
Summary 3(Bis(alkylthio)methylene)-3H-isobenzofuran-1-ones2a–e and 2-(bis(alkylthio)methylene)-3(2H)-benzofuranone derivatives4a–c are obtained by reaction of phthalides1a–d or 3(2H)-benzofuranone (coumaranone3), respectively, with carbon disulfide under basic conditions followed by alkylation. The reaction behaviour of the new compounds2 and4 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 of2a 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   

9.
Klyba  L. V.  Bochkarev  V. N.  Brandsma  L.  Nedolya  N. A.  Trofimov  B. A. 《Russian Chemical Bulletin》2001,50(12):2390-2393
The electron impact-induced fragmentation of 1-alkyl-2-(alkylthio)pyrroles is accompanied by rearrangements of the molecular and fragment ions with ring expansion.  相似文献   

10.
设计合成了25个新型1-取代吡唑甲酰基吡唑系列衍生物,化合物结构经1HNMR、元素分析、IR和MS确证.生物活性测试结果表明,该类化合物具有一定除草活性,讨论了其结构与活性的关系.  相似文献   

11.
(Alkylthio)chloroacetylenes are readily hydrochlorinated with hydrogen chloride in dioxane to form a mixture of (E)- and (Z)-1-(alkylthio)-1,2-dichloroethenes, as well as 1-(alkylthio)-1,1,2-trichloroethanes.  相似文献   

12.
《Mendeleev Communications》2021,31(6):856-858
An efficient synthesis of new (Z,E)-2-(alkylthio)alk-2-en-4-ynals by aldol condensation reaction of ynals with (alkylthio)-acetaldehydes using NaOH/DMF system has been developed.The reaction of these products with N,N-diphenylethylene-diamine and p-tosylmethyl isocyanide proceeds at the carbonyl group to form the corresponding imidazolidine and oxazole derivatives.  相似文献   

13.
G. Doleschall  K. Lempert 《Tetrahedron》1974,30(22):3997-4012
3 - Alkylthio - 6,7 - dihydro - [1.2.4]triazino - [1.6-c]quinazolin - 5 - ium - 1 - olates (3), prepared by condensation of 3 - alkylthio -6-(2- aminophenyl) - 1,2,4 - triazin - 5(2H) - ones (1) with aldehydes, ketones or their equivalents are transformed by thermolysis and/or acid treatment into 3 - alkylthio - [1.2.4]triazino[5.6-b]indoles (4) and/or 4-(5- alkylthio - s - triazol -3-yl)- quinolines (5). Alkylation and acylation reactions of the compounds 5 are discussed, as well as their NMR and UV spectra and those of their alkylation and acylation products.  相似文献   

14.
《Tetrahedron》1986,42(16):4511-4516
Treatment of 3-(alkylthio)indoles 3 with trifluoroacetic acid, neat (for 3a,b) or in dichloromethane solution (for 3c,d) at room temperature gave the corresponding 2-(alkylthio)-indoles in high yields (85–90%). The interconversion is complete and does not involve an acid-induced equilibrium between the two isomers; a mechanistic rationale is provided.  相似文献   

15.
The thermal isomerizations of N-[α-(alkylthio)alkyl]- and N-[α-(arylthio)alkyl]benzotriazoles have been investigated under N2 atmospheres (i) in toluene, xylene, MeOH, or EtOH, in the presence of acid catalysts and (ii) in the absence of solvent. The sulfide isomerization rates depend on the number of H-atoms carried by the C-atom attached to the N-atom of the benzotriazole: tertiary (no hydrogen) > secondary (1 hydrogen) > primary (2 hydrogens). The results support an isomenzation mechanism involving a heterolytic N? C bond cleavage with formation of sulfonium/carbonium and benzotriazolate ions.  相似文献   

16.
《Tetrahedron》1988,44(18):5921-5928
The nucleophilic substitution of activated 2-(alkylsulfinyl)thiophenes with alkyl- or arylmercaptans gives the corresponding 2-(alkylthio)- or 2-(arylthio)- substituted thiophenes. When thiolate anion is used instead of thiol, sulfoxide reduction is the main reaction.  相似文献   

17.
Fragmentation of molecular ions of 1,n-bis(alkylthio)alkanes (R1-S-(CH2)n-S-R2) occurs mainly by α- or β-cleavage to a sulphur atom. The ratio of fragments derived by α- or β-cleavage depends on the number of methylene groups (n) between the two sulphur atoms and on the alkyl groups R1 and R2. Generally β-cleavage induced fragmentation dominates for 1,2-bis(alkylthio)ethanes (n=2) leading to formation of thiiranium ions. Fragmentations derived by α-cleavage are predominant for all compounds with n=3; base peaks corresponding to [M-(R)]+ or [M-(2R)+(H)]+ are found which gives evidence for formation of five membered cyclic ions. Such fragmenss are less intense in compounds with n=4 whereas m all other compounds β-cleavage predominates if R = methyl, ethyl, n-propyl.  相似文献   

18.
Abstract

Metallation of alkylthio(ch1oro)phosphanes ClP(R′)S-R (R = i-Pr, tBu; R′ = tBu, St-Bu) and Cl2P-S-tBu with Na[M(CO)3Cp] (M = Cr, Mo, W) yields the metallo-(alkylthio) chloro-, metallo-bis(alkylthio)-, metallo-(alkylthio) (alkyl) phosphanes (la-f) or the bis(metallo)(alkylthiol phosphane (lg) respectively.  相似文献   

19.
Dimerization of methyl isothiocyanate under the action of potassium diisopropylamide followed by alkylation of the intermediate dithiolate gives 2,5-bis(alkylthio)-1-methylimidazoles in 71–74% yields. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 186–187, January, 1998.  相似文献   

20.
《Tetrahedron letters》1987,28(33):3805-3808
2-lithio-4,5-disubstituted-1,3-dithioles react with CS2 in thepresence of an excess organolithium reagents yielding a product of thiophilic addition; subsequent alkylation furnished a new series of2-[bis(alkylthio)methylene]-1,3-dithioles.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号