摘要:

AbstractDie Nitrierung des N‐Oxyds des 3‐Hydroxypyridins ist untersucht worden. Es wurde ein Mononitroderivat erhalten, welches sich als das N‐Oxyd des 2‐Nitro‐3‐hydroxypyridins erwies. Die Reduktion der Verbindung führte zum 2‐Amino‐3‐hydroxypyridin, die Reaktion mit PCl3und PBr3in Chloroform zur Bildung des 2‐Chlor‐3‐hydroxypyridins bzw.

ISSN:0165-0513    

DOI:10.1002/recl.19590780902

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY

摘要:

AbstractThe synthesis is described of 5‐hydroxypipecolic acid by reduction with sodium borohydride of the corresponding keto‐acid, which in turn was prepared from glutamic acid. This reduction proceeds without any appreciable formation ofallo‐isomer.The optical resolution is also described and the rotations of the optical antipodes are compared with those mentioned in the literature for the natural product.Further evidence is given for thecis‐OH/COOH configuration of theDL‐

ISSN:0165-0513    

DOI:10.1002/recl.19590780903

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY

摘要:

AbstractThe results are presented of investigations on preparing dihydrotachysterol2from dihydrovitamins D2‐I and D2

ISSN:0165-0513    

DOI:10.1002/recl.19590780904

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19590780905

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19590780906

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY

摘要:

AbstractThe decomposition of 1,2,3,4‐tetrahydronaphthyl‐1‐hydroperoxide (α‐tetralyl hydroperoxide) in the presence of catalytic amounts of zinc and magnesium stearate has been investigated in chlorobenzene and other solvents. For comparison, α, α‐dimethylbenzyl hydroperoxide (α‐cumyl hydroperoxide) and tert.butyl hydroperoxide have also been decomposed in the presence of the above catalysts.With zinc stearate, α‐tetralyl hydroperoxide predominantly yields phenolic products, the zinc soap apparently acting as a Lewis acid. Hydrogen is also obtained; it is probably generated by interaction of the phenolic aldehyde formed (γ‐(ortho‐hydroxyphenyl) butyraldehyde) and the hydroperoxide. The zinc stearate shows little effect, however, on the decomposition of α‐cumyl and tert.butyl hydroperoxide.Magnesium stearate causes a free‐radical chain decomposition of α‐tetralyl hydroperoxide (see Part IH. B. van Leeuwen et al., Rec. trav. chim.77, 17 (1958).) yielding mainly tetralone and tetralol. This metal soap also accelerates the decomposition of tert.butyl hydroperoxide and, to a less extent, of cumyl hydroperoxide.The catalytic influence of both magnesium and zinc stearate is markedly af

ISSN:0165-0513    

DOI:10.1002/recl.19590780907

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY

摘要:

AbstractThe theory of the stability of lyophobic colloids, as given byDerjaguinand byVerwey and Overbeekfor the flat‐plate model or the sphere model of colloidal particles, is applied to cylindershaped colloidal particles.Anisometry was taken into account by considering the interaction between two parallel particles and between two particles in a crossed position. Mathematical expressions are given for the repulsive and the attractive potential energy in these two cases. It should be inferred from these expressions that the behaviour of two parallel cylinders is intermediate between the behaviour of two flat plates and two spheres whereas two crossed cylinders behave in much the same way as two sphere

ISSN:0165-0513    

DOI:10.1002/recl.19590780908

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19590780909

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19590780910

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY

摘要:

AbstractThe development of a method, enabling the iodine‐values of micro amounts of fatty acids or their esters to be easily determined, is described. An excess of iodine is added to the sample and the amount of bound iodine determined spectrophotometricall

ISSN:0165-0513    

DOI:10.1002/recl.19590780911

出版商:WILEY‐VCH Verlag    

年代:1959

数据来源: WILEY