摘要:

AbstractThe K‐bands in the ultraviolet absorption spectra ofmetaandparasubstituted biphenylamines, dissolved in acidic media, appear to be essentially identical with each other and with that of their parent compound, biphenyl. Apparently the electronic interaction of the two aromatic rings is not markedly disturbed by the mere presence of positively charged ammonium groups, provided the molecules are able to assume a planar structure. As can be expected, however, appreciable hypsochromic shifts of the K‐bands become manifest when one or more of these groups are located at theorthopositions. Moreover, a buttressing effect is observed in the case where ammonium groups are present simultaneously in adjoiningmetapositions.A discussion of results takes into account both steric and electrostatic factors operating between the groups invol

ISSN:0165-0513    

DOI:10.1002/recl.19630820102

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractOn considering the hydrogen bonding ofn‐butanol with several ketones it appears that there is a regular increase in the value of the association constant on the introduction of methyl groups. Introduction of a phenyl group into a ketone brings about a decrease in hydrogen bonding. The cyclic ketones have high association constants, presumably due to their convenient structure for hydrogen bonding. An exception is formed by cyclopentanone, in which the sterical effect is counteracted by the larger double bond order of the>CO‐group. With sterically hindered molecules, such as di‐isopropyl ketone and di‐tert.‐butyl ketone there is less hydrogen bonding.From the results of the experiments no conclusions, as to the existence of a simple relation between K on the one side and the half widthv½ and the frequency‐shift Δvon the other,

ISSN:0165-0513    

DOI:10.1002/recl.19630820103

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractThis communication contains a description of the isolation of muscaridine from Amanita muscaria L. The constitution of muscaridin is established as erythro‐4,5‐dihydroxy‐n‐hexyltrimethylammoniumchloride. The synthesis, starting from 2,3‐dihydropyran, leads to racemic muscaridine. The resolution of racemic muscaridine succeeded with di‐p. toluyl‐L‐ tartaric acid and with di‐p. toluyl‐D‐tartaric acid. The synthetic product has the same RF‐value, a fully identical infrared spectrum and equal optical rotation as the natural base. The syntheses of threo‐4,5‐dihydroxy‐n‐hexyltrimethylammoniumchloride and of 5‐hydroxy‐n‐hexyltrimethyla

ISSN:0165-0513    

DOI:10.1002/recl.19630820104

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractThe main product of cyclisation ofN‐(m‐methoxyphenyl)‐N‐tosyl‐2‐aminopropionyl chloride is shown to beN‐tosyl‐7‐methoxy‐4‐oxo‐1,2,3,4‐tetrahydroquinoline. The 3‐cyano‐3‐methyl derivative of this quinolone, which was obtained from the latter in two steps, underwent a base catalyzed ring cleavage during an attempted Stobbe condensation. A mechanism for this cleav

ISSN:0165-0513    

DOI:10.1002/recl.19630820105

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19630820106

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractThe oxidation of cyclohexanol with nitric acid to adipic acid proceeds via two stable intermediates known from the literature1viz. 6‐hydroxyimino‐6‐nitro hexanoic acid and the hemihydrate of 1,2‐cyclohexanedione, two substances forming beside each other in a given ratio. This ratio can be calculated as a function, of the temperature and of the nitric acid and nitrous acid concentrations. The nitrous acid plays a very important part in the oxidation process. The oxidation of cyclohexanone proceeds in the same way as that of cyclohexanol, provided sufficient nitrous acid is present. In the absence of HNO2the oxidation does not proceed at all at low temperatures.The catalysts used ‐ ammonium vanadate and copper nitrate ‐ have very different functions. Under the influence of the vanadate the hemihydrate of cyclohexanedione is rapidly converted to adipic acid, whereas in the absence of vanadate this substance is slowly broken down to glutaric acid, succinic acid and oxalic acid. Copper is effective only at higher temperatures where it prevents the further break‐down of unstable

ISSN:0165-0513    

DOI:10.1002/recl.19630820107

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractThe preparation of dialkyl sulphides, selenides and tellurides by alkylating sodium sulphide, selenide or telluride, obtained from sodium and sulphur, selenium or tellurium in liquid ammonia, is very easily carried out and gives good yields. It is also possible to prepare and alkylate sodium disulphide and diselenide in liquid ammonia. The resulting dialkyl disulphides and diselenides in the reaction mixture can be converted simply and in good yields into the corresponding thiols and selenols.

ISSN:0165-0513    

DOI:10.1002/recl.19630820108

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

Abstract3,3′‐Diethyl‐Δ5,5′‐birhodanine (III, R  C2H5) was obtained as a by‐product from the reactions of 3‐ethylrhodanine with 2,4‐dinitrobenzaldehyde and 1‐chloro‐2,4‐dinitrobenzene under suitable conditions. The synthesis of 5‐arylidene substituted rhodanines was achieved from condensations of rhodanines with anils of aromatic aldehydes in glacial acetic acid. III (R  C2H5, CH2· CHCH2and CH2COOC2H5) were prepared by heating the appropriate rhodanines in pyridine containingp‐toluenesulphonyl chloride. Reduction of III with zinc and glacial acetic acid gave the corresponding 5,5′‐birhodanines, which were easily auto‐oxidised in solutions to the related III. Rhodanine and some of its congeners react with 1‐chloro‐2,4‐dinitrobenzene in ethanol containing sodium acetate to give 2,2′,4,4′‐tetranitrodiphenyl sulphide. The methylene group of 3‐aminorhodanine reacted withp‐nitrobenzaldehyde in boiling ethanol, while the amino group was attacked when the reaction was carried out in glacial acetic acid at room temperature. Pyridin

ISSN:0165-0513    

DOI:10.1002/recl.19630820109

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractBy infrared spectroscopy it is shown that trialkyltin acylates in the solid state occur as coordination polymers in which each tin atom is penta‐coordinated,viz. by three alkyl groups and two oxygen atoms belonging to different acylate groups. In apolar solvents or in the liquid state, however, the compounds are monomolecular and show resemblance to organic esters. Only in very concentrated solution or just above the melting point is association detected. In a search for the generality of the concept it was found that the occurrence of the polymeric crystal structure is counteracted by steric hindrance, that it does not occur with thio‐ or dithio‐acetates and, finally, that lead behaves like tin but germanium and silicon compounds are monomolecular throu

ISSN:0165-0513    

DOI:10.1002/recl.19630820110

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19630820111

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY