摘要:

AbstractThe anodic oxidation of adamantane‐2‐carboxylic acid in alcoholic solution leads to the formation of a mixture of radical‐derived and carbonium ion‐derived products, whereas adamantane‐1‐carboxylic acid yields only the carbonium ion‐derived product. (2‐Adamantyl)acetic acid gives chiefly the radical‐derived product in contrast to (1‐adamantyl)acetic acid, which yields carbonium ion‐derived products. In the electrolysis of 3‐(1‐adamantyl)propionic acid the radical‐derived compound is the main product. A rationalization of

ISSN:0165-0513    

DOI:10.1002/recl.19700890802

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19700890803

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19700890804

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractAfter prolonged irradiation oftrans‐α‐ionone(I) in ethanol two new isomers IV and V (cf. Table I) can be isol

ISSN:0165-0513    

DOI:10.1002/recl.19700890805

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractThe PMR spectral parameters of glycerol in a D2O solution are determined at different temperatures with a PMR apparatus operating at 220 Mc.With these parameters—assuming no correlation between rotational positions of the terminal CH2OH groups‐graphs are drawn of the population of a particular conformation as a function of theJtrans(JT) andJGauche(JG) coupling constants. If the conditionEα≤Eβ≤Eγis imposed the calculations show that the proportion of molecules in the αα conformation is about 20%.The result is verified from “trial” values forJTandJGtaken from the literature. IfEα

ISSN:0165-0513    

DOI:10.1002/recl.19700890806

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractThe detailed syntheses of 3‐deoxy‐D‐arabino‐ and 3‐deoxy‐D‐lyxo‐heptulosonic acids are described. Thearabinoisomer was purified by LLC on cellulose. In thearabinoseries an enolized 2‐keto‐1,4‐lactone and in both thearabinoandlyxoseries 2‐keto‐imido‐1,4‐lactones were isolated. The chemical and spectroscopic properties of these compounds are discussed. A number of other derivatives are described. The UV spectra of the semicarbazones of 2‐keto‐acids and their lactones or esters are discussed. The structure of a quinoxaline derivative of the 3‐deoxy‐D‐ara

ISSN:0165-0513    

DOI:10.1002/recl.19700890807

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

Abstract2‐Thienyl‐carbonyl compounds occur exclusively in the s‐transconformation as follows from NMR solvent shifts, temperature dependence of NMR spectra and nuclear Overhauser effects (NOE) as observed in some appropriately substituted 2‐thienyl‐carbonyl compounds. IR spectra are also in agreement with one (s‐trans) c

ISSN:0165-0513    

DOI:10.1002/recl.19700890808

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractThe addition compounds Br3PS · AlBr3, Br3PS · SbCl5and Br3PS · SO3were prepared and their thermal decomposition studied. The adduct Br3PS · AlCl3, unstable at room temperature, was found as an intermediate in the reaction of AlBr3with PSCl3. The first steps of the decomposition of Br3PS · SbCl5involve exchange of the halogens between P and Sb; finally, PSCl3, SbCl3, SbBr3and bromine are formed. The decomposition of Br3PS · SbCl5at elevated temperatures, however, gives PCl5· SbCl5, SbBr3, PSBr3and sulfur. Br3PS · SO3decomposes at 10° to SO2, POBr3and sulfur. The adducts Br3PO · AlBr3, Br3PO · 3 AlCl3, Br3PO · AlCl3, Br3PO · SbCl5, (Br3PO)2SbCl3, (Br3PO)2SbBr3, (Br3PO)2FeBr2, and Br3PO · 2 SO3(?) were also prepared‐most of them for the first time‐and their thermal decomposition studied. Infrared spectra of the adducts of PSBr3and POBr3with metal halides show that the sulfur (or oxygen) atom is coordinat

ISSN:0165-0513    

DOI:10.1002/recl.19700890809

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractThe rates of alkaline hydrolysis of the enantiomers of isopropylp‐nitrophenyl methylphosphonate have been measured with and without varying concentrations of α‐cyclodextrin (cyclohexa‐amylose) in aqueous 1.0MKCl solution at 25° in order to determine the origin of the acceleration of phosphate ester hydrolysis by cyclodextrins.The observed kinetics can be analyzed in terms of a non‐stereospecific binding of both enantiomers to α‐cyclodextrin prior to a nucleophilic reaction of α‐cyclodextrin predominantly with the (R)‐(‐)‐enantiomer. Dissociation constants (Kdiss) of the inclusion complexes and rate constants (k2) of the nucleophilic reaction are reported for the (R)‐(‐)‐enantiomer in dilute alkaline media.From the pH‐dependency of the rate of hydrolysis of the (R)‐(‐)‐enantiomer a kinetic pKavalue of 12.6 has been evaluated for the ionization of α‐cyclodextrin.The results also support the suggestion—proposed in the first paper of this series—to use the α‐cyclodextrin‐organophosphorus compound system as a simple model for inhibition o

ISSN:0165-0513    

DOI:10.1002/recl.19700890810

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19700890811

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY