Strain and Its Implications in Organic Chemistry: Organic Stress and Reactivity (Nato Science Series C:, 273)

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. Front Matter....Pages i-xviii Some Synthetic Implications of the Concept of Cyclopropyl Units as Pseudo-Functional Groups....Pages 1-23 Stereoselective Electrocyclizations and Sigmatropic Shifts of Strained Rings: Torquoelectronics !....Pages 25-37 The Preparation and Thermal Rearrangement of Functionalized 6-(1-Alkenyl)Bicyclo[3.1.0]Hex-2-Enes. Applications to synthesis....Pages 39-50 Synthesis with Donor-Acceptor-Substituted Vinylcyclopropanes....Pages 51-58 Synthesis of Functionalized Episulfides....Pages 59-75 Through-Bond Interaction Via Cyclobutane Relay Orbitals as a Means of Extending Conjugation....Pages 77-107 [2+3] Carbo- and Hetero-Cyclic Annulation in the Design of Complex Molecules. 1 ....Pages 109-115 Synthetic and Mechanistic Aspects of the Cyclopropene to Vinylcarbene Rearrangement....Pages 117-120 Generation and Interception of 1-Oxa-2, 3-Cyclohexadiene and 1,2,4-Cyclohexatriene....Pages 121-131 On the Relationship between Strain and Chemical Reactivity of Torsionally Distorted Carbon-Carbon Double Bonds....Pages 133-141 Photoinduced Single Electron Transfer from Strained Rings....Pages 143-167 Chemical Behaviour of Cation Radicals Derived from Strained Molecules in Solution. Spiro-Activation in the Cleavage of Some Arylcyclopropanes Upon Treatment with TCNE or DDQ....Pages 169-176 The Cyclopropyl Group in Studies of Enzyme-Catalysed Reactions....Pages 177-205 Intramolecular [2+2] Cycloadditons of Ketenes and Olefins....Pages 207-234 Strained Iminium Salts in Synthesis....Pages 235-254 The Generation and Rearrangement of 2-Diazocarbonyl Cyclobutanones: The Formation of 5-Spirocyclopropyl-2 (5h) Furanones....Pages 255-258 Computational Studies of Prismane, Helvetane/Israelane and Asterane....Pages 259-261 Cyclobutane-Cyclopentane Interconversion of Coordinated Adducts of Cycloheptatriene and Tetracyanoethylene Via the [2,2]-Sigmahaptotropic Rearrangement....Pages 263-268 Quest for Higher Prismanes....Pages 269-281 Planarizing Distortions in Polycyclic Carbon Compounds....Pages 283-296 Strain Release in Aromatic Molecules: The [2 n ] Cyclophanes....Pages 297-332 Trip Around the Three-Membered Cycles Syntheses....Pages 333-348 Experimental and Theoretical Studies of Bridged Cyclopropenes....Pages 349-359 From Bicyclo[1.1.0]Butanes to [n.1.1]Propellanes....Pages 361-381 New Aspects of Highly Strained Ring Chemistry....Pages 383-404 Strained Cage Systems....Pages 405-429 Studies on the Synthesis of Cyclopentanoic Sesquiterpenes Via Rearrangement Routes: (±)Modhephene and (±)Isocomene [1]....Pages 431-437 Directionality in Formation of Small Rings by Intramolecular Nucleophilic Substitution....Pages 439-446 Synthesis, Chiroptical Properties and Synthetic Applications of Perhydrotriquinacene-1,4,7-Trione....Pages 447-450 Reactions of Strained Carbon-Carbon Bonds with Metal Atoms....Pages 451-456 Cyclopropabenzenes and Alkylidenecyclopropabenzenes a Synergistic Relation between Theory and Experiment....Pages 457-462 Harnessing Strain: From [1.1.1] Propellanes to Tinkertoys....Pages 463-482 Synthesis of Cyclopropenes....Pages 483-483 How to Get Structures of Strained Compounds: Low Temperature Structures and X-X Electron Deformation Densities....Pages 485-488 Novel Intramolecular 1,1-Cycloadditions of Diazoallenes....Pages 489-492 Efficient Routes to Optically Active Strained Compounds....Pages 493-494 Anionic (3+2)-Cycloreversion of Strained Cage Nitriles....Pages 495-495 Reaction of an Angle Strained Cycloheptyne with a Stabilized Stannylene — Synthesis and X-Ray Structure of a Distannacyclobutene System....Pages 497-497 Structure and Reactivity of Small Heterocycles Containing Germanium Atoms....Pages 499-502 Relief of Strain Energy as Driving Force in Ring-Opening Polymerizations of a [1.1.1] Propellane....Pages 503-505 Diels-Alder Reactions of Siloxyallylidenecyclopropanes: Facile Syntheses of Spiro[2.5]Octan-3-Ones....Pages 507-508 Cyclopropyl Group Containing Amino Acids From α-Chlorocyclopropylidenacetates....Pages 509-512 Eliminative Fission of Strained Cycloalkoxides — The Question of Electrophilic Catalysis....Pages 513-513 Special Reactivity of 8,11-Dihalo[5]Metacyclophane....Pages 515-515 Small [N]Cyclophanes. Where is the Limit?....Pages 517-517 Back Matter....Pages 519-525 Proceedings of the NATO Advanced Research Workshop, Ratzeburg, Germany, August 28-September 2, 1988 Edited By Armin Meijere, Siegfried Blechert.