摘要:

AbstractPolynuclear carbonylmetal compounds provide convenient molecular analogues for the reactions occurring at metal surfaces during catalytic processes. Many properties of these cluster compounds are determined by the type and distribution of the ligands covering the metal polyhedral surface. Computer simulated space‐filling models of these complicated molecules provide readily assimilated information about the arrangement of surface ligands, and in many cases lead to conclusions not readily deduced from other approache

ISSN:0570-0833    

DOI:10.1002/anie.198608533

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractGreat advances have been made in the past decade in the field of NMR spectroscopy. Apart from the development of completely new areas of application, such as in solid‐state chemistry, in materials science, in physiological chemistry, and in medicine, with the introduction of new pulse spectroscopic methods and the application of high magnetic field strengths important progress has also been made in the traditional field of high‐resolution NMR spectroscopy. Thus, among other things, the observation of metal resonances has been facilitated and new areas of application have been opened up in inorganic and organometallic chemistry. In this review, recent detection methods for spin‐1/2 and quadrupolar metal nuclei are presented and discussed. The use of metal‐NMR spectroscopy with respect to problems of a typical chemical nature, mainly from the field of organometallics, is demonstrated for a number of selected metal nuclei (25Mg,27Al,49Ti,57Fe,59Co,61Ni,91Zr,103Rh, and195Pt). Relations found empirically between chemical shifts and coordination number, oxidation number, and electronic configuration of a metal bound in a complex are emphasized. Furthermore, cases in which the chemical shifts of metal nuclei can be interpreted in terms of the energy difference of frontier orbitals are presented. This aspect leads to the establishment of a relationship between chemical reactivity and NMR parameters for a series of related co

ISSN:0570-0833    

DOI:10.1002/anie.198608611

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe beginning student of organic chemistry is often bewildered by what appears to be an enormous maze of random structural variations and reactions that can be mastered only by tedious memorization. To the organic chemist, however, the same subject is often a beautifully ordered discipline of elegant simplicity. An important value of learning organic chemistry is the mastering of “organic thinking,” an approach to intellectual processing whereby the “sameness” of many families of structures and reactions is revealed. This article offers the author's personal views of organic thinking and explores the intellectual and scientific foundations of organic chemistry and of the powerful methods that provide the field with a platform for making rapid conceptual and experimental advances. It is proposed that these methods involve a geometric and topological approach to scientific reasoning within the framework of scientific paradigms that guide experimental design and execution. The basis of this approach is considered in relation to day‐to‐day thinking, problem solving, and the psychological drive for intellectual closure. The power of the approach is illustrated by the analysis of several photochemical and chemiluminescen

ISSN:0570-0833    

DOI:10.1002/anie.198608821

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198609021

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198609041

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198609051

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198609061

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198609071

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198609091

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198609101

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY