摘要:

AbstractThe concept of electron transfer catalysis (ETC), or more specifically “Double Activation Induced by Single Electron Transfer” (DAISET) gives an opportunity to connect experimental facts never previously correlated. The first activation results from the transfer of an electron to (or from) a molecular species; the second activation results from the build‐up of a reaction chain able to reproduce the species formed in the first step. The starting point of this review is the SRN1 mechanism where principle and experimental diagnostic criteria are critically discussed. The thermal and photochemical exchange and substitution reactions of PtIVcomplexes are then reviewed together with the exchange reaction [AuCl4]−/Cl−, reactions with Grignard reagents and other organometallic reagents, as well as the redox behavior of electronically excited organic compounds. Photochemical applications, including solar energy conversion are discussed. New aspects are also presented for the mechanistic problem “SN2 reaction or SET process?” Moreover, the concept has significance for SH2 reactions at metal centers, molecule‐induced homolyses, reactions of complexes, as well as electrochemical processes.–Unless otherwise specified, only double activation (DAISET) processes will be discusse

ISSN:0570-0833    

DOI:10.1002/anie.198200013

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractRibosome‐dependent protein synthesis in bacteria represents a complex sequence of reactions involving more than 150 compounds. The ribosome, constructed from 53 individual proteins and 3 nucleic acids, functions as the enzyme which catalyzes peptide bond formation. In contrast to most known enzymes the ribosome is “programmed” by the mRNA–the short‐lived transcript of DNA. The ribosome reads the nucleotide message of the mRNA and transforms its information into the amino acid sequence of a protein. In the course of this process, chemical bond energy is converted into directed mechanical motion. The model of protein biosynthesis on the programmable ribosome provides answers to the following questions: how is the mRNA framed into information units, how is the substrate specificity of the ribosome modulated by the codon of the mRNA, and how does the mRNA move with respect to the ribosome by one trinucleotide per peptide bo

ISSN:0570-0833    

DOI:10.1002/anie.198200231

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractThrough improved and novel syntheses, acyl cyanides—especially aliphatic acyl cyanides—have become so readily accessible that numerous synthetic applications present themselves. The present review surveys the development of the chemistry of the acyl cyanides during the last 25 years. The syntheses and most important reaction possibilities of RCOCN are outlined in four large schemes: reactions of the CO‐ and CN‐groups—in each case with preservation of the carbon skeletal framework—as well as acylations with cleavage

ISSN:0570-0833    

DOI:10.1002/anie.198200361

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractAfter a decade, the first storm of development in high performance liquid chromatography seems to be abating. Providing the stationary phase and eluent are optimized, most routine analytical and semi‐preparative separation problems require columns having between 1000 and 10000 theoretical plates. Commercial apparatus and columns completely satisfy these requirements. For many separation problems the efficiency of the columns on offer is greater than required. Since optimal (not maximal) separation is required with shorter analysis times, the column inlet pressure is increased in order to increase the eluent velocity, while at the same time reducing the column efficiency. The same result can be obtained by using shorter columns and lower pressures. Since inlet pressures of more than 100 bar are seldom required in routine analysis, the term “high pressureliquid chromatography” is a misnomer.—It is probable that difficult separation problems, where several 100 000 theoretical plates are required, will be studied in the next phase of development. It can be shown using nomograms that such problems can be solved within acceptable time limits using inlet pressures of less than 500 bar. Further possible directions of development are in

ISSN:0570-0833    

DOI:10.1002/anie.198200501

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractThe complete manuscript of this communication appears in:Angew. Chem. Suppl. 1982, 153. DOI:10.1002/anie.198201530

ISSN:0570-0833    

DOI:10.1002/anie.198200622

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198200631

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198200641

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractThe complete manuscript of this communication appears in:Angew. Chem. Suppl. 1982, 34. DOI:10.1002/anie.198200340

ISSN:0570-0833    

DOI:10.1002/anie.198200652

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractThe complete manuscript of this communication appears in:Angew. Chem. Suppl. 1982, 85. DOI:10.1002/anie.198200850

ISSN:0570-0833    

DOI:10.1002/anie.198200661

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractThe complete manuscript of this communication appears in:Angew. Chem. Suppl. 1982, 91. DOI:10.1002/anie.198200910

ISSN:0570-0833    

DOI:10.1002/anie.198200671

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY