Since the pioneering work by Sarel and co-workers on the iron carbonyl p- moted transformation of vinylcyclopropanes and related compounds [1],a - riety of transition metal complexes have been examined to achieve effective - tivation of the vinylcyclopropane-cyclopentene rearrangement which usually requires pyrolytic conditions. These reactions have been applied to natural product synthesis in some cases and have already been reviewed in several - cellent articles [2-4]. Contrary to the well-established chemistry of the vinylcyclopropanes, the corresponding reactions of alkynyl- and propadienylcyclopropanes have not, until recently,received much attention.We present here a summary of the recent efforts towards the development of transition metal promoted transformation of these molecules with a brief survey of the corresponding thermal reactions. 2 Rearrangement of Alkynylcyclopropanols Unlike the well-known chemistry of the vinylcyclopropane-cyclopentene - arrangement, there is no general method for the rearrangement of alkyn- cyclopropane to cyclopentene derivatives.One specific example is the pyrolysis of 1-ethynyl-2-methylcyclopropane to methylenecyclopentene and other c- pounds [5]. At 530 C, 1-ethynyl-2-methylcyclopropane (1) undergoes a [1,- hydrogen shift to give hexa-1,2,5-triene ( 2),which further isomerizes to met- lenecyclopentenes 3 and 4 in 38 and 29% yield,respectively (Scheme 1).

With contributions by Lau, K.-L.; Tam, K.-F.; Trost, B.M.; Wong, H.N.C.

Carbon Rich Compounds are defined here as carbon skeletons with a carbon-to-hydrogen ration of 1: (less than or equal 1), which includes all-carbon compounds, i.e. carbon allotrope. The current volume complements Topics in Current Chemistry Volume 196, which focussed on polycyclic aromatic compounds, by presenting an overview of the exciting recent results that have been achieved acetylene-based carbon rich structures. Leaders in the field present timely reviews on the synthesis, properties and chemistry of cyclic and macrocyclic oligoacetylenic structures, molecular scaffolding, arylene- and arylenevinylene-based oligomers and polymers, as well as carbon rich compounds from ethynylated Pi-complexes.

The topic .Stress and Strain. of this conference was ideally constrasted by the remoteness and quiet atmosphere of the meeting place Hotel Seehof In Ratzeburg, a small medieval town situated on a peninsula in lake "Kuchensee. east of Hamburg In northern Germany. With the participation of 53 leading experts from all over the world, the workshop covered the widest possible range from the advancement of bonding theory, new mechanistic insights into chemical transformations and physical properties of highly strained compounds to their use as building blocks In organic synthesis and even as probes Into the detection of enzyme mechanisms. Because of their specific reactivities small ring units can uniquely play their role in the construction of composite functionalities. Such functionalities can increase the elegance In natural and non-natural products syntheses, since they help to develop more convergent synthetic routes and Improve the necessary chemo-, regio-and stereo-selectivity. This book presents all of the 20 Invited lectures and is complemented with short versions of 12 contributed papers and 13 poster presentations. I am convinced that it will stimulate further rapid development of this field of organic chemistry, which recently has seen extensions into the bioorganic area as well as towards new materials. In fact, several .supra-natural" -at first sight exotic -compounds are already available In useful quantities and are being exploited to create vastly new molecular devices, i. e. compounds with unprecedented molecular functions and polymers with unconventional properties."

Carbon Rich Compounds are defined here as carbon skeletons with a carbon to hydrogen ratio of 1:(=

Carbon Rich Compounds are defined here as carbon skeletons with a carbon to hydrogen ratio of 1: (=centro"-polyhydrindanes as well as oligoquinanes, in particular highly unsaturated ones, are discussed.

Organic Synthesis via Organometallics is an interdisciplinary project sponsored by the Volkswagen Stiftung to stimulate research and discussion of advances in the field. To improve international communication , leading experts are invited to regular symposia. In this volume, 17 lectures presented at the second symposium in Wurzburg, October 1988, are collected. From the topics covered it complements the previous volume, edited by A. de Meijere and H. tom Dieck.

More and more possible applications of organometallic compounds in organic synthesis have been uncovered and a growing number of scientists are attracted to this area of research. This book presents an state-of-the-art account of the successful application of main- and transition metal mediated syntheses. It will stimulate new ideas and initiate further research in all areas of this fascinating chemistry.

In this second, completely revised and enlarged edition, Francois Diederich is joined by Armin de Meijere in bringing together in two comprehensive volumes everything of importance related to C-C and C-N cross-coupling reactions.
The range of applications covered extends from the synthesis of complex natural materials via supramolecular chemistry right up to materials science. Internationally renowned experts pass on to the reader the current level of knowledge, while critical analyses of the latest developments and applications allow users to quickly decide for themselves on which strategies are available for solving their synthesis problems. In particular the experimental guidelines for key reactions developed by the authors for the widest possible range of applications testify to the practical advantages this handbook offers every organic chemist.

This three volume book is the follow-up handbook to the bestselling volume "Metal-Catalyzed Cross-Coupling Reactions", the definitive reference in the field. In line with the enormous developments in this area, this is not a new edition, but rather a new book in three volumes with over 50% more content. This new content includes C-H activation, shifting the focus away from typical cross-coupling reactions, while those topics and chapters found in de Meijere/Diederich's book have been updated and expanded. With its highly experienced editor team and the list of authors reading like an international Who's-Who in the field, this work will be of great interest to every synthetic chemist working in academia and industry.

The topic ·Stress and Strain· of this conference was ideally constrasted by the remoteness and quiet atmosphere of the meeting place Hotel Seehof In Ratzeburg, a small medieval town situated on a peninsula in lake "Kuchensee· east of Hamburg In northern Germany. With the participation of 53 leading experts from all over the world, the workshop covered the widest possible range from the advancement of bonding theory, new mechanistic insights into chemical transformations and physical properties of highly strained compounds to their use as building blocks In organic synthesis and even as probes Into the detection of enzyme mechanisms. Because of their specific reactivities small ring units can uniquely play their role in the construction of composite functionalities. Such functionalities can increase the elegance In natural and non-natural products syntheses, since they help to develop more convergent synthetic routes and Improve the necessary chemo-, regio-and stereo-selectivity. This book presents all of the 20 Invited lectures and is complemented with short versions of 12 contributed papers and 13 poster presentations. I am convinced that it will stimulate further rapid development of this field of organic chemistry, which recently has seen extensions into the bioorganic area as well as towards new materials. In fact, several ·supra-natural" -at first sight exotic -compounds are already available In useful quantities and are being exploited to create vastly new molecular devices, i. e. compounds with unprecedented molecular functions and polymers with unconventional properties.