摘要:

AbstractA series of 4‐N‐substituted 1,2,3‐benzotriazin‐4(3H)‐imines was prepared by aminolysis of 1,2,3‐benzotriazine‐4(3H)‐thione and its 6‐chloro derivative with primary aliphatic amines. The reaction was shown to be sensitive to amine structure and to reaction conditions. Frequently observed tar formation is attributed to instability resulting from the cryptodiazonium character of the triazine ring. Spectral data substantiate the thiono and imino structures of the starting compounds and products, respectively, i

ISSN:0022-152X    

DOI:10.1002/jhet.5570060601

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

Abstract5‐Isoxazolylhydrazines III were obtained from 5‐isoxazolones I,viathe 5‐haloisoxazoles II. The decomposition of the tosyl derivatives of III results in unambigous syntheses of 3,4‐disubstituted iso

ISSN:0022-152X    

DOI:10.1002/jhet.5570060602

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractThe structure of the product of the reaction of 2‐aminobenzimidazole with ethyl aceto‐acetate has been established by NMR spectroscopy as 2‐melhylpyrimido[1,2‐a]benzimidazol‐4‐ol (III). 7(and 8)‐Chloro‐2‐methylpyrimido[l,2‐a]benzimidazol‐4‐ol (VI and VIII, R  OH), 2‐(trifluoromethyl)pyrimido[i,2‐a]benzimidazol‐4‐ol (X), 2,7,8‐trimethylpyrimido[1,2‐a]benzimidazol‐4‐ol (XII), 2‐benzyl‐1,2,3,4‐tetrahydropyrido[4′,3′:4,5]pyrimido[1,2‐a]benzimidazol‐12‐ol (XIII), 1,2,3,4‐tetrahydrobenzimidazo[2,1‐b]quinazolin‐12‐ol (XIV), and 2,3‐dihydro‐1H‐cyclopenta[4,5]pyrimido[1,2‐a]benzimidazol‐11‐ol (XV) were prepared in a similar manner. Chlorination of III, VI and VIII, XV, and 5‐methyl‐s‐triazolo[1,5‐a]pyrimidin‐7‐ol (XXV, R  OH) with phosphorus oxychloride afforded the corresponding chloroheterocycles, which were condensed with the appropriateN,N‐dialkylalkylenediamine orNα,Nα‐diethyl‐6‐methoxytoluene‐α,3‐diamine to give various 4‐\documentclass{article}\pagestyle{empty}\begin{document}$ \left[\!\left[ {} \right.\right. $ \end{document}[(dialkylamino)alkyl]amino\documentclass{article}\pagestyle{empty}\begin{document}$ \left[\!\left[ {} \right.\right. $ \end{document}‐2‐methylpyrimido[1,2‐a]benzimidazoles (Va‐e, VII, IX), 11‐\documentclass{article}\pagestyle{empty}\begin{document}$ \left.\left. {} \right]\!\right]$ \end{document}[(dialkylamino)alkyl]amino\documentclass{article}\pagestyle{empty}\begin{document}$ \left[\!\left[ {} \right.\right. $ \end{document}‐2,3‐dihydro‐1H‐cyclopenta[4,5]‐pyrimido[1,2‐a]benzimidazoles (XVIa and b), and 7‐\documentclass{article}\pagestyle{empty}\begin{document}$ \left[\!\left[ {} \right.\right. $ \end{document}[(dialkylamino)alkyl]amino\documentclass{article}\pagestyle{empty}\begin{document}$ \left.\left. {} \right]\!\right]$ \end{document}‐5‐methyl‐s‐tr

ISSN:0022-152X    

DOI:10.1002/jhet.5570060603

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractCondensation of α‐halocarbonyl compounds and 2‐mercaptobenzimidazole gives thiazolo‐[3,2‐a]benzimidazoles. This condensation occurred at the mercapto group of the benzimidazole followed by cyclization to form the thiazole ring. This was confirmed by the examination of the mass spectra of 2‐ and 3‐methylthiazolo[3,2‐a]benzimidazoles, 2‐ and 3‐phenylthiazolo[3,2‐a]‐benzimidazoles,

ISSN:0022-152X    

DOI:10.1002/jhet.5570060604

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractN,N‐Dialkylamides, pyrones, and phosphorus oxychloride react to give pyranylidene chloroiminium salts. The chlorine atom of these salts is readily displaced by nucleophiles to yield a variety of pyranylidene derivative

ISSN:0022-152X    

DOI:10.1002/jhet.5570060605

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractSeveral chloro‐ and dichloro‐3‐alkyl‐1,2,3‐benzotriazin‐4(3H)ones have been prepared by diazotization of methyl anthranilates. A brief study was made of factors affecting the formation of 3‐allyl‐1,2,3‐benzotriazin‐4(3H)one from methyl anthranilate. Good nmr evidence was obtained to substantiate the previously proposed methyl 2‐(3‐allyltriazeno)benz

ISSN:0022-152X    

DOI:10.1002/jhet.5570060606

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractA study was made of the formation of thieno[2,3‐c]pyridine (1) from hydrogen sulfide and 4‐vinylpyridine in a flow system at 630°. 2‐(4‐Pyridyl)ethanethiol and bis‐2‐(4‐pyridyl)ethyl sulfide were found to be likely intermediates. Based on these studies, there was devised a two‐step practical preparative method for I (optimum overall yield 58%) which consists of preliminary conversion of 4‐vinylpyridine to benzyl 2‐(4‐pyridyl)ethyl sulfide and subsequent thermolysis (at 6

ISSN:0022-152X    

DOI:10.1002/jhet.5570060607

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

Abstract5‐Hydroxy‐7‐alkyl‐2‐phenyl‐7H‐pyrrolo[2,3‐d]pyrimidine‐6‐carbonitriles (VIIb‐d) and 5‐hydroxy‐2‐phenyl‐7H‐pyrrolo[2,3‐d]pyrimidine‐6‐carboxylic acid, ethyl ester (VIIa) were prepared from 5‐carbethoxy‐4‐chloro‐2‐phenylpyrimidine (IV)via4‐[(cyanomethyl)alkylamino[‐2‐phenyl‐5‐pyrimidinecarboxylic acid, ethyl esters (Vb‐d) and 4‐[(carboxymethyl)amino]‐2‐phenyl‐5‐pyrimidinecarboxylic acid, diethyl ester (Va), respectively. The hydroxy group of the pyrrolo‐[2,3‐d]pyrimidines could be methylated, acetylated and tosylated. Hydrolysis of 5‐methoxy‐7‐methyl‐2‐phenyl

ISSN:0022-152X    

DOI:10.1002/jhet.5570060608

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractThe mass spectra of 4‐selenochromanone, 4‐hydroxyselenocoumarin, and 3,3′‐methylene bis(4‐hydroxyselenocoumarin) have been determined, and the fragmentation pathways of these substances under electron‐impact are discussed. A strong tendency to form the benzoselenophen ring was noted in all

ISSN:0022-152X    

DOI:10.1002/jhet.5570060609

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractThe addition of diazomethane to a series of substituted styrenes has been kinetically investigated with emphasis on polar, solvent, and solvation effects. Although the reaction is generally insensitive to solvent polarity, a sizeable substituent effect (ρ = +0.90) has been observed. Also, a sizeable increase in rate was generally observed in protic solvents such as water, and a considerable rate enhancement occurred in the case of nitrostyrene in the dipolar aprotic solvent, dimethylformamide. The results are discussed in terms of a concerted mechanism involving a partially‐charged transition state II, with negative charge formation on the α‐carbon of the styrene.The methoxystyrene offers an exception to the Hammett equation and the unexpectedly high rate constant for this compound could be discussed in terms of a possible participation of the highly nucleophilic resonance form ofp‐methoxystyrene and an α‐additionviathe transition state III. However, solvation effects in dimethylformamide (failure to obtain the anticipated rate increase) and the formation of a 3‐substituted pyrazoline adduct from the cycloaddition reaction indicate steric control to predominate over electronic factors and β‐addition to prevail unequivocally.It is proposed that solvation effects in protic solvents can be utilized to advantage in cycloaddition reactions leading to 1‐pyrazolines, for which no other routes are available at

ISSN:0022-152X    

DOI:10.1002/jhet.5570060610

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY