ISSN:0570-0833    

DOI:10.1002/anie.199417891

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractThe transition metal catalyzed reaction of α‐diazo carbonyl compounds has found numerous applications in organic synthesis, and its use in either heterocyclic or carbocyclic ring formation is well precedented. Early work in this area made use of insoluble copper catalysts. Although these catalysts are still employed today, their use has decreased significantly with the advent of homogeneous copper catalysts and catalysts based on other metals. The discovery that RhIIcarboxylates facilitate nitrogen loss from diazo compounds rekindled significant interest in the field of diazo/carbenoid chemistry. Since the realization that RhIIcarboxylates are superior catalysts for the generation of transient electrophilic metal carbenoids from α‐diazo carbonyl compounds, intramolecular carbenoid addition and insertion reactions have assumed strategic importance in CC bond‐forming reactions in organic synthesis. In contrast to other catalysts that are suitable for carbenoid reactions of diazo compounds, those constructed with the dirhodium(II) framework are most amenable to ligand modifications that, in turn, can influence reaction selectivity. This article will emphasize the chemical behavior of transition metal carbenoid complexes that are greatly affected by the nature of the ligand groups attached to the metal center. Much of the discussion will center on the ability of the dirhodium(II) ligands to determine reaction preference toward different functional groups on the same

ISSN:0570-0833    

DOI:10.1002/anie.199417971

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractThe troposphere, the part of the earth's atmosphere which is closest to the surface, harbors important life processes. This important part of our environment contains primarily nitrogen and oxygen. In addition, it comprises a number of other substances, which are generally present in low concentrations. The primary reason for the low content of these trace components is the activity of a diatomic radical, namely the hydroxyl radical. OH is the main constituent of the oxidizing potential of the troposphere and causes the transformation of many trace components into water‐soluble forms, which can then rain out and be removed from the troposphere. OH has therefore acquired the title “detergent of the atmosphere”. The knowledge of local hydroxyl radical concentrations is therefore an important piece of information, especially with respect to model calculations for atmospheric chemistry. The OH concentration is very low and its determination represents a significant analytical challenge. It is controlled in a delicate manner by chemical formation and decomposition reactions, which interact to create a recycling process in the tropos

ISSN:0570-0833    

DOI:10.1002/anie.199418161

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.199418271

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.199418301

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.199418321

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.199418351

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractFor corrigendum see DOI:10.1002/anie.199423481

ISSN:0570-0833    

DOI:10.1002/anie.199418371

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.199418391

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.199418411

出版商:Hüthig&Wepf Verlag    

年代:1994

数据来源: WILEY