摘要:

AbstractEpoxides, in which R can represent the groupingsare converted by KO‐t‐C4H9in dimethyl sulfoxide into derivatives of furan or dihydrofuran and/or alcohols with the enyne system CCCCCOH. The analogous episulfides () give, in low yield, the expected thiophen

ISSN:0165-0513    

DOI:10.1002/recl.19760950402

出版商:WILEY‐VCH Verlag    

年代:1976

数据来源: WILEY

摘要:

AbstractReaction of dimethyl sulfoxide with two equivalents of lithium in liquid ammonia gives a solution of lithium methanesulfenate which can be alkylated or benzylated to yield the corresponding sulfoxide.

ISSN:0165-0513    

DOI:10.1002/recl.19760950403

出版商:WILEY‐VCH Verlag    

年代:1976

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19760950404

出版商:WILEY‐VCH Verlag    

年代:1976

数据来源: WILEY

摘要:

AbstractEnol ethers of cyclic β‐diketones can be alkylated and acylated in high yields atC(6). When this position is blocked, alkylation takes place atC(

ISSN:0165-0513    

DOI:10.1002/recl.19760950405

出版商:WILEY‐VCH Verlag    

年代:1976

数据来源: WILEY

摘要:

AbstractThe kinetics of the reaction between aromatic amines and aromatic acid chlorides in hexamethylphosphoric triamide (HMPT) have been studied by stopped‐flow spectrophotometry using an acid‐base indicator to follow the change in H⊕ during the reaction.Measurements on bifunctional amines and acid chlorides,e.g. p‐phenylenediamine(PPD) and terephthaloyl dichloride (TDC) have shown that the NH2groups in PPD react approximately 12 times as fast as the NH2group in the intermediate product, while the acid chloride groups in TDC and intermediate product have equal reactivities.It has been found for all reactions studied that protonation of the NH2groups by the H⊕ produced is very important.The influence of substituents could be analysed by two Hammett relations. The reaction of substituted anilines with benzoyl chloride could be described by the relation logkR= −1.4σ+R+ 2.10 and the reaction of substituted benzoyl chlorides with aniline by the relation logkR=

ISSN:0165-0513    

DOI:10.1002/recl.19760950406

出版商:WILEY‐VCH Verlag    

年代:1976

数据来源: WILEY

摘要:

AbstractThe condensation of amines of the general type H2N‐(CH2)n‐D‐(CH2)m‐NH2(D is an aromatic system with electron donor properties) with 1,2:4,5‐benzene‐tetracarboxylic dianhydride or with 1,8:4,5‐naphthalene‐tetracarboxylic dianhydride under high dilution conditions is shown to lead to the formation of electron donor(D)‐acceptor(A) cyclophanes of the typecontaining the 1,2:4,5‐benzene‐tetracarboxylic diimide or the 1,8:4,5‐naphthalene‐tetracarboxylic diimide group as an electron acceptor.The fragmentation pattern of the cyclophanes upon electron impact is studied and found to agree completely wit

ISSN:0165-0513    

DOI:10.1002/recl.19760950407

出版商:WILEY‐VCH Verlag    

年代:1976

数据来源: WILEY

摘要:

AbstractLes constantes de vitesse d'addition neutre,ko, et acido‐catalysée,kH, de l'hydroxylamine sur l'acétone, la cyclohexanone, la cyclopentanone, la cycloheptanone et sur neuf acétophénones ont été mesurées dans l'eau à 25°. Les valeurs des constantes ρ de Hammett sont respectivement égales à +0,78 et +0,45 pour la réaction neutre et la réaction acido‐catalysée. Le mécanisme des deux additions et la structure de leurs états de transition sont discutés. Dans les deux cas le processus de transfert de proton parait être “concerté” et l'état de transit

ISSN:0165-0513    

DOI:10.1002/recl.19760950408

出版商:WILEY‐VCH Verlag    

年代:1976

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19760950401

出版商:WILEY‐VCH Verlag    

年代:1976

数据来源: WILEY