摘要:

AbstractElucidation of the structures of organic acids and bases with the aid of their acidity constants is greatly hindered by their low solubilities in water and by the small quantities of material normally available. Apparent acidity constants K*can be determined potentiometrically on small samples (about 0.5 mg) for many classes of compounds of medium acidity. The apparent acidity constants K *MCSdetermined in the solvent system methyl cellosolvel water can be correlated, in a similar manner to thermodynamic quantities, with structural parameters (e.g. Hammett's σ*and Taft's σ*values). K *MCSvalues can yield information on the axial or equatorial position of carboxyl groups in cyclohexanecarboxylic

ISSN:0570-0833    

DOI:10.1002/anie.196406611

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractOn oxidation of graphitic carbon, acidic surface oxides (or hydroxides in the presence of water) are formed at the boundaries of the carbon layers. It was found that the reaction of oxygen with microcrystalline carbon at 400–450°C yields four groups of different acidities. One strongly acidic group and one weakly acidic carboxyl group have been detected, as well as a phenolic hydroxyl group; a carbonyl group is probably also present. With dissolved oxidizing agents, one equivalent of another strongly acidic carboxyl group is formed in addition at room temperature. The possible constitutions of the acidic surface oxides are discussed. Chemically detectable surface oxides are also formed on the surface of diamond. In the presence of oxygen at 800–900°C under reduced pressure, diamond is transformed into black carbon. Surface oxides play a part in this transform

ISSN:0570-0833    

DOI:10.1002/anie.196406691

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractPhosphorylating agents are compounds capable of transferring the group (HO)2P(O) in free or esterified form. Numerous phosphorylating agents can be classified into PXYZ systems, in which the element or group Z must be capable of accommodating the electrons of the PX bond. Systematic classification of PXYZ compounds and numerous examples of phosphorylation in chemistry and biochemistry ar

ISSN:0570-0833    

DOI:10.1002/anie.196406781

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractTernary and quasiternary compounds consist of either one cationic and two anionic,or one anionic and two cationic components. The size of the ions and the bonding forces between them determine the structure of the compounds. A compound is regarded as a complex when its lattice contains structural groups in which the interaction between the constituent atoms is substantially greater than or different from that between these structural groups and the other components of the compound. Metallo‐complexes are built up of one cationic and two anionic components; in contrast to the complexes with cationic central atoms which have been thoroughly investigated, they contain an anionic central atom surrounded by cationic ligands. A list is given of many compounds which can be formulated as metallo‐complexes after discussion of methods for their preparation and their chemical properties; the reason that only few metals can function as ligands of an anionic central atom is deduced from the pertinent crystal structu

ISSN:0570-0833    

DOI:10.1002/anie.196406861

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196406932

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196406942

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196406952

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196406962

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196406972

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196406982

出版商:Hüthig&Wepf Verlag    

年代:1964

数据来源: WILEY