The Chemistry of Zirconacycles and 2,6-Diazasemibullvalenes (eBook)

Synthesis, Structures, Reactions, and Applications in the Synthesis of Novel N-Heterocycles

Shaoguang Zhang (Autor)

eBook Download: PDF

2014 | 2015
XI, 173 Seiten
Springer Berlin (Verlag)
978-3-662-45021-5 (ISBN)

Infos

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.

Inhalt

Introduction to Zirconacycle Chemistry.- Zirconocene-Mediated Cyclization of Bis(alkynyl)silanes and Nitriles: Synthesis of N-Heterocycles and Isolation, Characterization and Synthetic Application of Zr/Si-containing Reactive Intermediates.- Bulky-Nitrile Coordination Induced Skeleton Rearrangement of Zr/Si-containing Metallacycles and Selective Synthesis of 5-Azaindoles.- Introduction to Semibullvalenes and Azasemibullvalenes.- Diazasemibullvalenes: Synthesis, Structure, Theoretical Analysis and Computational Chemistry.- Diazasemibullvalenes: Reaction Chemistry and Synthetic Application.

Produkt-Details

• Erscheint lt. Verlag: 5.11.2014
• Reihe/Serie: Springer Theses
• Reihe/Serie: Springer Theses
• Zusatzinfo: XI, 173 p. 131 illus., 5 illus. in color.
• Verlagsort: Berlin
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Chemie ► Organische Chemie
• Themenwelt: Technik
• Schlagworte: 2,6-diazasemibullvalene • Chemical Transformer • Cope Rearrangement • Multi-component Cyclization • N-heterocycle • Poly-cyclic Skeleton • Reactive Intermediate • Zirconacycle • Zirconacyclobutene-silacyclobutene fused Compound
• ISBN-10: 3-662-45021-6 / 3662450216
• ISBN-13: 978-3-662-45021-5 / 9783662450215