摘要:

AbstractThe quantum yield of the photo‐decomposition of some aromatic diazonium salts in solution is estimated, using light with a wavelength of 3650 Å.The photo‐decomposition of phenyl‐amino benzene diazonium sulphate is proposed as a suitable actinometer.The quantum yield of the photochemical isomerisation of stable p‐methoxy‐benzenediazo‐cyanide was found to b

ISSN:0165-0513    

DOI:10.1002/recl.19520710902

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY

摘要:

AbstractThe preparation of a number of 2,3‐dialkyl(aryl)thio‐naphthoquinones‐1,4 and 2,3,5,6‐tetraalkyl(aryl)thio‐naphthoquinones‐l,4 i

ISSN:0165-0513    

DOI:10.1002/recl.19520710903

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY

摘要:

AbstractThe dehydrogenation of hydrocarbons by means of tetrachloro‐p‐benzo‐quinone (chloranil) was found to proceed according to the overall equation: hydrocarbon + quinone → dehydrogenated hydrocarbon + hydroquinone. The kinetic order of the reaction proved to be bimolecular. The rate of reaction depended on the concentration of hydrocarbon and of quinone.A correlation was found to exist between the oxidation‐reduction potentials of a number of substituted quinones and their activity in the dehydrogenation of tetralin to na

ISSN:0165-0513    

DOI:10.1002/recl.19520710904

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY

摘要:

AbstractThe substituted thiophene‐1.1‐dioxides are stable substances; they react with maleic anhydride, with nucleophilic reagents, and with reducing agents.Phenylated and methylated thiophene‐1,1‐dioxides and maleic anhydrides give—with one exception—endovinylene‐cyclohexane‐tetracarboxylic anhydrides; the intermediate endosulphonyl compounds could not be isolated.Most of the sulphones are not stable towards alkalis and amines. Definite reaction products were isolated in a few cases, e.g. from 3,4‐dimethylthiophene‐1,1‐dioxide and piperidine. Another synthesis of this sulphone is the dehydrohalogenation of 3,4‐dibromo‐3,4‐dimethyl‐thiacyclopentane‐1,1‐dioxide.Many of these sulphones can be reduced to real thiophene derivatives. In one case both the reduction and the hyd

ISSN:0165-0513    

DOI:10.1002/recl.19520710905

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY

摘要:

AbstractIn the preparation of II, just as in the earlier dimerization coupled with hydration of methylchavicol, , the two inactive stereoisomers were obtained. By reduction of the alcohol function they yielded, in accordance with the nature of the isomerism in question, the same final product.

ISSN:0165-0513    

DOI:10.1002/recl.19520710906

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY

摘要:

AbstractThe nature and the velocities of the reactions occurring in concentrated solutions of urea and formaldehyde may be very similar to what is found in dilute systems.A rapid initial reaction between urea and formaldehyde, as reported in literature, was not observed and is shown to be due to the analytical methods used.

ISSN:0165-0513    

DOI:10.1002/recl.19520710907

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY

摘要:

AbstractBy splitting off water from the intermediate hydroxy‐compounds in the Vitamin A‐series allylic rearrangement takes place into the cyclohexene ring. This rearrangement occurs throughout the whole Vitamin‐A‐series‐ with those hydroxy‐intermediates wherein the hydroxy‐group is in an allyl position with regard to the double bond in the cyclohexene ring.The reason why so many attempts to prepare synthetic Vitamin A in reasonable yields, starting with “key” intermediates other than the C14aldehyde, lead to a failure,

ISSN:0165-0513    

DOI:10.1002/recl.19520710908

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY

摘要:

AbstractThe preparation of 1‐methyl‐2‐hydroxy‐3‐diazobenzene‐5‐sulphonic acid, starting from o‐cresol, is described. With a small quantity of a strong acid a suspension of 1‐methyl‐2‐hydroxy‐3‐aminobenzene‐5‐sulphonic acid in a solution of sodium nitrite gives the sodium s

ISSN:0165-0513    

DOI:10.1002/recl.19520710909

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY

摘要:

AbstractA description is given of the synthesis of the thio‐analogues of ergosterol and 7‐dehydrocholesterol from these two compou

ISSN:0165-0513    

DOI:10.1002/recl.19520710910

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY

摘要:

AbstractA description is given of the condensation of amino‐acetonitriles with phenols according to the method ofHouben‐Hoesch. The condensations have led to the preparation of a number of compounds of the type:A number of s̀‐amino‐acetophenones have been converted into compounds with sympathomimetic activity. An investigation has been made into the conditions and the mechanism of the synthesis, and the influence of substituents in the benzene nucleus on the reactivity of the phenol component. A discussion is devoted to the electronic interpretation of the synthesis according toHoube

ISSN:0165-0513    

DOI:10.1002/recl.19520710911

出版商:WILEY‐VCH Verlag    

年代:1952

数据来源: WILEY