摘要:

AbstractThe base‐catalyzed cyclization of someN‐propargylamides to oxazoles has been studied in the presence of sodium hydride and potassium carbonate. The α‐arylsubstituted propargylamides1c‐d(Ar =p‐OMeC6H4(1c), C6H5(1d), andp‐O2NC6H4(1e)) cyclized with markedly higher rates (1e>1d>1c) than the unsubstituted and α‐methyl substituted propargylamides1aand1b. A1H nmr spectroscopic experiment demonstrated the presence of an allenic intermediate in the potassium carbonate‐catalyzed ring closure of1e. The observed rank order of reactivities correlates well with the acidities of the respective propargylic hydrogens of the amides and with the ability of the ring closed intermediates to stabilize an oxazole anion. The results demonstrate that the base‐catalyzed formation of oxazoles from propargylamides may proceedviaan a

ISSN:0022-152X    

DOI:10.1002/jhet.5570260201

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractThe reaction of 4‐amino‐1H‐1,5‐benzodiazepine‐3‐carbonitrile1with hydroxylamine provided the ring‐opened hydroxylamine adduct2which was converted to 2‐benzimidazolidinylidene‐3‐hydroxyiminopropio‐nitrile4in hydrochloric acid. The reaction of 4‐ethoxycarbonylamino‐1H‐1,5‐benzodiazepine‐3‐carbonitrile6aorN‐(3‐cyano‐1H,5‐benzodiazepin‐4‐yl)‐N′‐ethylurea6bwith hydroxylamine afforded 5‐(o‐aminoanilino)‐4‐cyanoisoxaz

ISSN:0022-152X    

DOI:10.1002/jhet.5570260202

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractSome 8‐ or 9‐halobenzofuro[2,3‐b]quinolines (1a, 8‐F, 8‐C1, 9‐F, 9‐Cl) and 9‐halobenzofuro[2,3‐b]quinoline‐11‐carboxylic acid (1b, F, Cl) were synthesized from 6‐ or 7‐halo‐3‐(2‐methoxyphenyl)‐2‐oxo‐1,2‐dihydroquino‐line‐4‐carboxylic acids (3). And, some 9‐halo‐11(6H)‐benzofuro[2,3‐b]quinolinone (8, F, Cl, Br) and 2‐halo‐6(5H)‐benzofuro[3,2‐c]quinolinone (9, F, Cl, Br) were synthesized from 6‐halo‐4‐hydroxy‐3‐(2‐methoxyphenyl)‐2(1H)‐quinolinone (7), and they were converted to the corre

ISSN:0022-152X    

DOI:10.1002/jhet.5570260203

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractSome benzofuro[3,2‐b]quinoline derivatives1a‐dand3awere synthesized by condensation of 2‐amino‐benzaldehyde, 2‐aminoacetophenone, 2‐aminobenzophenone, isatin, or 2‐aminobenzoic acid with 3(2H)‐benzofuranone. The benzofuroquinolinone3awas also obtained from 2‐aminobenzoic acid and phenoxy‐acetyl chloride in two steps and converted to 10‐chloro derivative1e. Similarly, some 8‐halobenzofuro[3,2‐b]‐quinoline derivatives1d,eand3a(X = F, Cl, Br, I) were synthesized from 5‐haloisatin or 2‐amino‐5‐halo‐benzoic acid. And benzofuro[3,2‐b]quinolines1a‐ethus obtained

ISSN:0022-152X    

DOI:10.1002/jhet.5570260204

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractAminophenyl‐X‐azolopyridines (X = O, S, NH) are interesting intermediates for the synthesis of disperse azo dyes and, provided the pyridine nitrogen is quaternized, of their cationic counterparts. A set of novel amines and nitro derivatives is described, and their physical properties and spectral parameters are discussed in comparison with those of analogous compounds. Some dyes in the oxazole series function as probes of the reactivity of the pentatomic r

ISSN:0022-152X    

DOI:10.1002/jhet.5570260205

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

Abstract4‐Pyrimidinamines have been reacted with 3‐bromo‐1‐phenylpropane‐1,2‐dione to give a series of (imidazo[1,2‐c]pyrimidin‐2‐yl)phenylmethanones. The dione also reacted with ethyl amidinoacetate to yield ethyl 2‐amino‐5‐benzoylpyrrole‐2‐carboxylate which was used to prepare a series of 6‐ben

ISSN:0022-152X    

DOI:10.1002/jhet.5570260206

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractThe heterocyclization reaction of arylsulfonylhydrazones from alkyl substituted 1,2‐cyclohexanediones is sensitive to the steric requirements of the alkyl groups. A mechanism for the cyclization in acidic medium is also reporte

ISSN:0022-152X    

DOI:10.1002/jhet.5570260207

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

Abstract1‐Azatricyclo[3.3.1.13‐7]decan‐4‐one (4‐oxo‐1‐azaadamantane) and 1‐azatricyclo[3.3.1.13‐7]decane‐4‐α(β)‐ol (4‐α‐(β)‐hydroxy‐1‐azaadamantane) have been studied by1H and13C nmr methods. From this study several stereo and stereoelectronic effects have been deduced. The complete proton and carbon chemical shift assignments for the title compounds have been made, with the

ISSN:0022-152X    

DOI:10.1002/jhet.5570260208

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

Abstract5‐Cyano‐3,4‐dihydro‐6‐phenyl‐2‐substitutedpyrimidin‐4‐ones1a‐creacted with phosphorus oxychloride to give the corresponding 4‐chloropyrimidine derivativesIIa‐c. CompoundsIIa‐creacted with aniline and hydrazine to yield the 4‐anilino,IIIa,e, and 4‐hydrazino,IIIb‐dderivatives. The 4‐hydrazino analoguesIIIb,ccould be converted into the triazolo[4,3‐c] and tetrazolo[4,5‐c]pyrimidinesIVandVby the action of carbon disulphide and nitrous acid, respectively. The reaction ofIIb,cwith phenylhydrazine afforded directly the 5‐amino‐4,6‐diphenyl‐6H‐2‐substitutedpyrazolo[3,4‐d]pyrimidinesVIa,b. The 4‐chloro derivativeIIareacted with antrhanilic acid to form the 5‐cyano‐2,4‐diphenyl‐6‐(o‐carboxyphenylamino)pyrimidineVIII, which could be cyclised into the 4‐cyano‐1,3‐diphenyl

ISSN:0022-152X    

DOI:10.1002/jhet.5570260209

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractCertain 4‐substituted 1H‐pyrrolo[2,3‐b]pyridines (7‐azaindoles) undergo a nucleophilic substitution‐rearrangement upon treatment with various primary amines at elevated temperatures to yieldN‐1‐substituted 4‐amino‐1H‐pyrrolo[3,2‐c]pyridines (5‐azaindoles). Treatment of the same 7‐azaindoles with secondary amines under the same reaction conditions led to simple nucleophi

ISSN:0022-152X    

DOI:10.1002/jhet.5570260210

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY