Download or read book The Chemistry of Zirconacycles and 2 6 Diazasemibullvalenes written by Shaoguang Zhang and published by Springer. This book was released on 2014-11-05 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, the author introduces two strategies used to construct various types of N-heterocycles, based on the chemistry of zirconacycles and 2,6-diazasemibullvalenes. In the first part, the author presents the development of multi-component cyclization of a zirconacyclobutene-silacyclobutene fused compound, nitriles and unsaturated compounds. These reactions provide synthetically useful methodology for various N-heterocycles such as 3-acyl pyrrole, pyrrolo[3,2-d]pyridazine and dihydropyrroloazepine, which are all difficult to synthesize by other means. The isolation and characterization of the key three-fused-ring Zr/Si-containing intermediates are also described in detail. These results show that the zirconacyclobutene-silacyclobutene fused compound behaves as a “chemical transformer” upon treatment with various substrates via the “coordination-induced skeleton rearrangement” mechanism. In the second part, the author demonstrates the synthesis and isolation of a series of 2,6-diazasemibullvalenes (NSBVs) from the reaction of 1,4-dilithio-1,3-dienes and nitriles, highlighting the significant progress made for the first time in this work: (1) determination of X-ray crystal structure of a substituted 2,6-diazasemibullvalene; (2) measurement of the activation barrier of its rapid intramolecular aza-Cope rearrangement in solution; (3) exploration of several reaction types of NSBV with diverse ring-expansion products and “bowl-shape” or “cage-shape” N-containing polycyclic skeletons; (4) demonstration of the localized structure as the predominant form and the homoaromatic delocalized structure as a minor component in the equilibrium using theoretical analysis. Based on well-founded results, this work sheds new light on this controversial topic.

Download or read book Strategic Applications of Named Reactions in Organic Synthesis written by Laszlo Kurti and published by Elsevier. This book was released on 2005-04-29 with total page 808 pages. Available in PDF, EPUB and Kindle. Book excerpt: Kurti and Czako have produced an indispensable tool for specialists and non-specialists in organic chemistry. This innovative reference work includes 250 organic reactions and their strategic use in the synthesis of complex natural and unnatural products. Reactions are thoroughly discussed in a convenient, two-page layout--using full color. Its comprehensive coverage, superb organization, quality of presentation, and wealth of references, make this a necessity for every organic chemist. * The first reference work on named reactions to present colored schemes for easier understanding* 250 frequently used named reactions are presented in a convenient two-page layout with numerous examples* An opening list of abbreviations includes both structures and chemical names * Contains more than 10,000 references grouped by seminal papers, reviews, modifications, and theoretical works * Appendices list reactions in order of discovery, group by contemporary usage, and provide additional study tools* Extensive index quickly locates information using words found in text and drawings