Organosilicon Chemistry I11

From Molecules to Materials

Edited by Norbert Auner and Johann Weis

@ WILEY-VCH Weinheim . Berlin . New York . Chichester * Brisbane Singapore * Toronto

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Organosilicon Chemistry I11

Edited by N. Auner and J. Weis

6B WILEY-VCH

This Page Intentionally Left Blank

Organosilicon Chemistry I11

From Molecules to Materials

Edited by Norbert Auner and Johann Weis

@ WILEY-VCH Weinheim . Berlin . New York . Chichester * Brisbane Singapore * Toronto

Prof. Dr. N. Auner Institut fur Chemie Fachinstitut fur Anorganische und Allgemeine Chemie Humboldt-Universitat zu Berlin Hessische StraBe 1-2 D-10115 Berlin Germany

Dr. J . Weis Wacker-Chemie GmbH Geschaftsbereich S Werk Burghausen Johannes-HeS-StraBe 24 D-84489 Burghausen Germany

This book was carefully produced. Nevertheless, authors, editors and publisher do not warrant the information contained therein to be free of errors. Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inad- vertently be inaccurate.

Editorial Director: Dr. Anette Eckerle Production Manager: Hans-Jochen Schmitt

Library of Congress Card No. applied for.

A catalogue record for this book is available from the British Library.

Deutsche Bibliothek Cataloguing-in-Publication Data: Organosilicon chemistry : from molecules to materials / ed. by Norbert Auner und Johann Weis. - Weinheim ; New York ; Basel ; Cambridge ; Tokyo : VCH

3 (1997) ISBN 3-527-29450-3

0 WILEY-VCH Verlag GmbH, D-69469 Weinheim (Federal Republic of Germany), 1998

Printed on acid-free and chlorine-free paper.

All rights reserved (including those of translation in other languages). No part of this book may be reproduced in any form - by photoprinting, microfilm, or any other means - nor transmitted or translated into machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even when not specifically marked as such, are not to be considered unprotected by law. Printing: betz-druck, D-64291 Darmstadt Bookbinding: Wilh. Osswald, D-67433 Neustadt Printed in the Federal Republic of Germany

This volume summarizes the lectures and poster contributions of the III. Miinchner Silicontage that were held in April 1996. This symposium as well as the two predecessors (in 1992 and 1994) were again jointly organized by the Gesellschaft Deutscher Chemiker and Wacker-Chemie GmbH. The number of participants from industry and university, especially of students and young scientists, was again pleasing and is convincing evidence for the great interest in this meeting; in addition it was appreciation for the effort of the organizers. Moreover the book reviews of Organosilicon Chemistry 11 - From Molecules to Materials from all over the world have encouraged us to continue the series with the current issue. The volumes of Organosilicon Chemistry are not considered to be textbooks in a common sense which should help students to pass basic examinations. These contributions from internationally renowned experts and researchers in a fascinating part of the rapidly growing field of main group chemistry describes current trends in organosilicon chemistry and provides summaries of the latest knowledge in this area. However, in order to facilitate students and "non-silicon" scientists an easier access to the ongoing research on the basis of the relevant historical background, we decided to split this volume in two parts, each with a comprehensive introduction, one on molecular and one on polymer and solid state (organo)silicon chemistry. During the I. Miinchner Silicontage the Wacker Silicon-Preis was awarded to the two pioneers of silicone chemistry - Prof Dr. Richard Muller and Prof. Dr. Eugene Rochow on the occasion of the SO* anniversary of the "Direct Process". In the course of the II. Miinchner Silicontage this award was conferred on Prof Dr. Edwin Hengge, Technische Universitat Graz, for his hndamental work in polysilane chemistry. At the III. Miinchner Silicontage Prof Dr. Hubert Schmidbaur was honoured by presenting the Wacker Silicon-Preis for his outstanding contributions in the field of the synthesis and characterization of organosilicon "molecules and materials". Right in the middle of the editorial phase of this volume, we were sad to hear of the unexpected decease of our friend Prof. Dr. Edwin Hengge. With him the organosilicon community has lost a passionate lecturer and researcher, unforgettable for his integrity and charming personality. Therefore it is the editors special wish that this volume shall keep alive the memory of an excellent organosilicon chemist! Collecting and publishing these papers it is our main intention to encourage students and young scientists to focus on organosilicon chemistry and to continue the work in the future! We want to light a beacon - outstanding success in the last few years should not deceive us, that there are still a lot of challenging problems to be solved in the hture: this includes basic research as well as the development of new materials. In August 1997

Pro$ Dr. Norbert Auner Dr. Johann Weis

Acknowledgment

First of all we would like to thank the numerous authors for their intense cooperation, which made this overview of current organosilicon chemistry possible. The tremendous work load to achieve the attractive layout of this volume was mainly performed by Dr. Claus-Rudiger Heikenwalder and Dr. Mathias Kersten. We thank both for their admirable engagement!

Pro$ Dr. Norbert Auner Humboldt-Universitat zu Berlin

Dr. Johann Weis Wacker-Chemie GmbH Munchen

Contents

I Fascinating Organosilicon Compounds

Introduction .................................................................................................................................. 1 N Auner, G. Fearon, J. Weis

More Compelling Evidence that Silicon is Better Than Carbon: The Thermal ............................... 17 Isomerization of Olefins to Carbenes T. J. Barton, J. Lin, S. Qadi-Maghsoodi, M. D. Power, X. Zhang, Z. Ma, H. Shimizu, M. S. Gordon

NMR and Quantum Chemical Characterization of Silicon-Substituted Carbocations .................... .25 H,-U. Siehl, B. Miiller, 0. Malkina

Matrix Isolation Studies of the Reactions of Silicon Atoms G. Maier, H. P. Reisenauer, H. Egenolf

.3 1

Cycloaddition Reactions of Dimethylaminomethylsilylene with Dienes and Heterodienes ............. .36 S. Meinel, J. Heinicke

Do Unsubstituted Silacyclobutadienes Exist? , . , . , , , , , , . , , . , G. Maier, H. P. Reisenauer, J. Jung, A. Meudt, H. Pacl

.39

A Thermally Stable Silylene: Reactivity of the Bis(amino)silylene Sl[tN(CH2tBu))2C&- 1,2] ..... .44 B. Gerhus, P. B. Hitchcock, M. F. Lappert

Pyrido[b]- 1 ,3,2h2-diazasilole: The First Stable Unsymmetrical Silylene ... A. Oprea, J. Heinicke

50

A New Route to Silaheterocycles: Heterobutadiene Cycloaddition .............................................. .53 H. H. Karsch, P. Schliiter

Base Coordination: A Way to Nucleophilic Silylenes? ................................................................. .58 J. Belzner

Isoelectronic Replacement of Si by P’: A Comparative Study of the Structures of the ................... 65 Spirocyclic En Compounds E[C(PMe2),(X)I2 (E = Si, Ge, Sn; X = PMe2,SiMes) and a Novel Spirocyclic 10 e-Phosphorus Cation(Pm) P[C(PPh2)2(SiMe3)]2’ H. H. Karsch. E. Witt

The Main Group Carbonyls mi-CO and R2Si-CO: An Ab Initio Study ....................................... 70 M. Tacke

VIII Contents

Unprecedented Multistep Reactions of Decamethylsilicocene, (Me5Cs)zSi:, with C02, CSZ, ......... .76

COS, RNCS (R = Me, Ph), with CF3CCCF3, and with HMn(C0)5 P. Jutzi, D. Eikenberg

Rearrangement of Bis(hypersily1)silylene and Related Compounds - An Unusual Way to ............. .82

Three-Membered Rings K. W. Klinkhammer

Oxidation of Silenes and Silylenes: Matrix Isolation of Unusual Silicon Species ........................... .86 WO Sander, M. Trommer, A. Patyk

New Silaheterocycles: Formation and Properties ............................ E. Kroke, M. Weidenbruch

.95

Cycloaddition Reactions of 1,l-Dichloro-2-neopentyl-l -den with Monoterpenes ....................... 10 1 C.-R. Heikenwalder, N. Auner

Silaspirocycles as Precursors for a 2-Silaallene ........................................................................... 106 B. Goetze, B. Herrscha), N . Auner

Catalytic Carbon-Carbon Hydrogenation of Silicon-Functionalized Olefins ................................. 1 13 H.-U. Steinberger, N. Auner

Dieno- and Enophilicity of Sila-, Germa-, and Stannaethenes ...................................................... 117 N. Wiberg, S. Wagner

Iminosilanes and Silaamidides: Synthesis and Reactions ............................................................. ,120 J. Niesmann, A. Frenzel, U. Klingebiel

Metastable Compounds Containing Silicon-Phosphorus and Silicon-Arsenic Multiple Bonds: .... .126 Syntheses, Structures and Reactivity M. Driess, S. Rell, U. Winkler, H. Pritzkow

Silole and Germole Dianions and their Dilithium Derivatives - Are they Aromatic? .................... 144 T. Miiller, Y. Apeloig, H. Sohn, R. West

Supersilylmetal Compounds ...................................................................................................... ,152

N. Wiberg, K. Amelunxen, H. Noth, A. Appel, M. Schmidt, K. Polborn

Trialkylsilyl Substituted Homobimetallic Phosphanides of the Alkaline Earth Metals as .............. ,157 well as Zinc M. Westerhausen, B. Rademacher, M. Hartmann, M. Wieneke, M. Digeser

The Tris(trimethylsily1)silyl Substituent: An Old Hat With A New Feather .................................. 162 A. Heine, L. Lameyer, D. Stalke

Contents IX

Functionalized Trisilylmethanes and Trisilylsilanes as Precursors of a New Class of ................... ,172 Tripodal Amido Ligands M. Schubart, B. Findeis, H. Memmler, L. H. Gade

Methoxy-bis[tris(trimethylsilyl)silyl]methane: The First Geminal Di(hypersily1) Compound ........ .178 E. Jeschke, T. Gross, H. Reinke, H. Oehme

The Use of the Tris(trimethylsily1)silyl Group in Stabilization of Low Valent Gallium ................. 182 Compounds W. Kostler, G. Linti

Synthesis, Structure, and Reactions of Tris(trimethylsi1yl)silyl Gallanes and Gallates .................. .189

H. Urban, R. Frey, G. Linti

Novel Pathways in the Reactions of Vinylsilanes with Lithium Metal ......... A. Maercker, K. Reider, U. Girreser

....... 195

New Organosilicon Reagents : Synthesis, Structure, and Reactivity of ....................................... .206 (Lithiomethyl)(aminomethyl)silanes B. C. Abele, C. Strohmann

(Pheny1thiomethyl)silanes as New Bihnctional Assembling Ligands for the Construction .......... .2 1 1 of Heterometallic Complexes M. Knorr, S. Kneifel, C. Strohmann

Synthesis of 1,3-Disilacyclobutanes, 1,3-Digermacyclobutanes, and 1 -Germa-3 -sila- ................. .2 17 cyclobutanes with New 1,3-Dimetallated Organoelement Building Blocks C. Strohmann, E. Wack

Trialkylsilyldiazomethane Derivatives: Wonderfhl Chemical Building Blocks ............................. .223 G. Bertrand

A New Route to Silaheterocycles: Nucleophilic Aminomethylation ............................................ ,237 H. H. Karsch, K. A . Schreiber

Infrared and Raman Spectra, ab initio Calculations, and Rotational Isomerism of Methylated Disilanes K. Schenzel, A . Jahn, M. Ernst, K. Hassler

1,2-Di-tert-butyltetrafluorodisiIane: A Highly Fluxional Molecule ............ R. Zink, K. Hassler, N. W. Mitzel, B. A. Smart, D. W. H. Runkin

,241

,248

Amino-Substituted Disilanes by Reductive Coupling .................................................................. ,254

S. Mantey, J. Heinicke

X Contents

Multifunctional Disilane Derivatives ....................................... H. Stuger, P. Lassacher, E. Hengge

New Transition Metal Substituted Oligosilanes .....

W Palitzsch, U. Bohme, G. Roewer

,257

,262

Regiospecific Chlorination and Oxygenation of Pentahydridodisilanyl Complexes of Iron .......... ,267 and Ruthenium S. Moller, H. Jehle, W. Malisch, W. Seelbach

Inter- and Intramolecular Oxidative Addition of Si-H Bonds ..................................................... ,271 R. Karch, H. Gilges, U. Schubert

Novel Synthetic Approach to Molybdenum-Silicon Compounds: Structures and ........................ ,275

Reactivities P. Jutzi, S. H. A. Petri

Unexpected Reactivity of Bis-1,2-[(bromodiphenyl)methyl]-l, 1,2,2-tetramethyldisilane .............. 28 1 F. Pillong, 0. Schutt, C. Strohmann

Trichlorosilane/Triethylamine - An Alternative to Hexachlorodisilane in Reductive ................... ,286 Trichlorosilylation Reactions? L.-P. Muller, A. Zanin, J. Jeske, P. G. Jones, W.-W. du Mont

Disproportionation of Chloromethyldisilanes using Lewis Base Heterogeneous Catalysts - ........ .29 1 A Way to Influence the Polymer Structure T Lange, N Schulze, G. Roewer, R. Richter

Supersilylated Bromodisilanes, Cyclotri-, and Cyclotetrasilanes ................................................. ,296 N Wiberg, H. Auer, Ch. M. M. Finger, K. Polborn

Syntheses and 29Si NMR Spectra of Halogenated Trisilanes and Cyclopentasilanes .................... ,301 K. Hassler, W Kdl, U. Poschl

Chlorination of Methylphenyloligosilanes: Products and Reactions C. Notheis, E. Brendler, B. Thomas

Selective Hydrogenation of Methylchlorooligosilanes ........

U. Herzog, G. Roewer

Electrochemical Formation of Cyclosilanes ....................................................

S. Graschy, C. Grogger, E. Hengge

Undecamethylcyclohexasilanyl Derivatives of Tin(1V) and Lead(1V) F. Uhlig, U. Hermann, K. Klinkhammer, E. Hengge

,307

,312

.317

... 322

Contents XI

New Results in Cyclosilane Chemistry: Siloxene-like Polymers A. Kleewein, b! Patzold, E. Hengge, S. Tasch, G. Leising

,327

Stepwise Synthesis of Functional Polysilane Dendrimers , , , , , . . . . _ _ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,333 C. Marschner, E. Hengge

Synthesis and Reactivity of Novel Polysilynes and Branched Copolysilanes . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . ,337 W. Uhlig

Unusual Polyhedra by Lithiation of Silazanes . . . . . . . . . . .

G. Becker, S. Abele, U. Eberle, G. Motz, W. Schwarz

Isomeric Halosilylhydroxylamines: Preparation and Thermal Rearrangements R. WolfgYamm, U. Klingebiel

Reactions of Hydridosilylamides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K. Junge, N. Peulecke, K. Sternberg, H. Reinke, E. Popowskr

,342

.348

,353

Silylhydrazines: Precursors for Rings, Hydrazones and Pyrazolones . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . ,358 C Drost, U. Klingebiel, H. Witte-Abel

Products from Multiple Insertion Reactions between Diisocyanates and Antiheteroaromatic . . . . . . ,364 1,4-Bis(trimethylsilyI)- 1,4-dihydropyrazine T. Sixt, F. M. Hornung, A. Ehlend, W. Kaim

Some Surprising Chemistry of Sterically Hindered Silanols . . . .. . . . .. . .. . . . . . . . . . . P. D. Lickiss

Silanetriols: Preparation and Their Reactions . . . . . . . . . . . . . . . . . _ _ R. Murugavel, A. Voigt, M. G. Walawalkar, H. W. Roesky

Silsesquioxanes as Crown Ether Analogs ..... . . . . . . . . . . . . . . . . . .. . . b! Dittmar, H. C. Marsmann, E. Rikowski

Azomethine-Substituted Organotrialkoxysilanes and Polysiloxanes . . . .. . . . . . . . . . . . . F. Mucha, G. Roewer

.369

,376

,395

,400

On the Reaction of ( t B ~ ~ S n 0 ) ~ with Organochlorosilanes. Simple Formation of . . . . . . . . . . . . . . . . . . . . . . . . ,403 [(tBu2SnO)2(tBu2SiO)] J. Beckmann, K. Jurkschat, D. Schollmeyer

Silanols and Siloxanes Substituted with the Chiral Iron Fragments Cp(OC)(RPhzP)Fe . . . . . . . . . . . . . . . ,407 [R = Ph, (H)(Me)(Ph)C(Me)N] W. Malisch. M Neumayer, K. Perneker. N. Gunzelmann. K. Roschmann

XI1 Contents

Si-H Functionalized Ferrio-Trisiloxanes C~RS(OC)~F~-S~(M~)(OS~M~~H)~ (R = H, Me) ........... ,412 J. Reising, W. Malisch, R. Lankat

Novel Siloxy-Bridged Di-, Tri-, and Tetranuclear Metal Complexes from Ferrio- and ................ .4 15 Tungsten-Silanols W. Malisch, J. Reising, M. Schneider

The 2-Dimethylaminomethyl-4,6-dimethylphenyl Substituent' A New Intramolecular Coordinating System with High Steric Demand U. Dehnert, J. Belzner

418

Reaction Behaviour of Hypervalent Silanes ....

H. Lang, E. Meichel, M. Weinmann, M. Melter ,423

Investigations of Nucleophilic Substitution at Silicon: An Unprecedented Equilibrium ............... ,429 between an Ionic and a Covalent Chlorosilane D. Scharv J. Belzner

Ligand Exchange Mechanism in Novel Hexacoordinate Silicon Complexes ................................ .43 5 D. Kost, S. Krivonos, I. Kalikhman

Ligand Exchange via Coordinative Si-N Bond Cleavage and Pseudorotation in Neutral ............ .446 Pentacoordinate Silicon Complexes I. Kalikhman. D. Kost

Phosphine Coordination to Silicon Revisited .............................................................................. .452 G. Muller, M. Waldkircher, A . Pape

Novel Sila-Phospha-Heterocycles and Hypervalent Silicon Compounds with Phosphorus .......... .460 Donors H. H. Karsch, R. Richter, E. Witt

Germanium Analogues of Zwitterionic Spirocyclic h5Si-Silicates ............ J. Heermann, R. Tacke, P. G. Jones

,466

I1 Silicon Based Materials

Introduction .............................................................................................................................. ,471 N Auner, G. Fearon, J. Weis

The Direct Process to Methylchlorosilanes: Reflections on Chemistry and Process .................... ,478 Technology B. Pachaly, J . Weis

Contents XI11

On the Nature of the Active Copper State and on Promoter Action in Rochow Contact ............ .484 Masses H. Ehrich, D. Born, J. Richter-Mendau, H. Lieske

On the Acid- and Base- Catalyzed Reactions of Silanediols and Siloxanediols in Water .............. ,496 H. Kelling, W. Rutz, K. Busse, C. Wendler, D. Lange

Trace Analysis of Mono- and Trifhctional Groups in Polydimethylsiloxanes Using ................... .500 Reaction Headspace GC J. Graphoff

Synthesis and Investigation of the Surface Active Properties of New Silane Surfactants ............. ,504 S. Stadtrniiller, K.-D. Klein, K. Koppen, J. Venzrner

Carbohydrate-Modified Siloxane Surfactants: The Effect of Substructures on the ...................... .S 10

Wetting Behaviour on Non Polar Solid Surfaces R. Wagner, L. Richter, Y. Wu, J. WeiJmiiller, J. Reiners, K.-D. Klein. D. Schaefer, S. Stadtmiiller

Synthesis and Application of o-Epoxy-Functionalized Alkoxysilanes G. Speweslage, K. Stoppek-Langner, J. Grobe

Diffuse Reflectance IR and Time-of-Flight SIMS Investigation of Methoxysilane SA-Layers on Silica and Alumina K. Stoppek-Langner, K. Meyer, A. Benninghoven

515

520

Ether-Substituted Triethoxy- and Diethoxymethylsilanes: Precursors for Hydrophilic, ............... .526 Elastic Consolidants for Natural Stones R. Fabis, C. Zeine, J. Grobe

Organosilicon Compounds for Stone Impregnation - Long-Term Effectivity and ....................... .53 1 Weathering Stability C. Bruchertseifer, S. Briiggerhoff; K. Stoppek-Langner, J. Grobe, M. Jursch, H.-J. Gotze

Studies on the Regioselectivity of the Hydroformylation with Alkenylalkoxysilanes . , . , , , . , . , , . _ _ . _ _ . . ,538 M. Wessels, J. Grobe

Novel Precursors for Inorganic-Organic Hybrid Materials ......................................................... ,543 S. Kairies, K. Rose

Mesomorphic Properties of Poly(diphenylsi1oxane) .................................................................... .5 50

B. R. Harkness, M. Tachikawa, I. Mita

Applications of Silicone Elastomers for Electrical and Electronic Fields ..................................... ,555 M. Takahashi

XIV Contents

Cyclic Liquid Crystalline Siloxanes: Chemistry and Applications ..........

F.-H. Kreuzer, N. Haberle, H. Leigeber, R. Maurer, J. Stohrer, J. Weis

Modified Polydimethylsiloxanes with Fluorescent Properties B. Strehmel, C. W. Frank, W. Abraham, M. Garrison

,566

,587

Sensitized Cationic Photocrosslinking of a,o-Terminated Disiloxanes: Cation Formation .......... ,594 in Nonpolar Media U. Miiller, A. Kunze, Ch. Herzig, J. Weis

Cationic Photoinitiators for Curing Epoxy-Modified Silicones ................................................... ,605 C. Priou

Photoconductivity in Polysilylenes: Doping with Electron Acceptors ......................................... .6 17 A. Eckhardt, V. Herden, W. Schnabel

Functionalized Polycarbosilanes as Preceramic Materials S. Back, H. Lang, M. Weinmann, W. Frosch

,622

Novel Polyorganoborosilazanes for the Synthesis of Ultra-High Thermal Resistant Ceramics ..... ,628 L. M. Ruwisch, W. Dressler, S. Reichert, R. Riedel

Precursors for Silicon-Alloyed Carbon Fibers ............................................................................ ,632 J. Dautel, W. Schwarz

One-Pot Syntheses of Poly(diorganylsily1ene-co-ethyny1ene)s . W. Habel, A. Moll, P. Sartori

,638

Localization Phenomena of Photogenerated Charge Carriers in Silicon Structures: .................... ,643 From Organosilicon Compounds to Bulk Silicon T. Wirschem, S. Veprek

Functionalized Structure-Directing Agents for the Direct Synthesis of Nanostructured .............. ,649 Materials P. Behrens

Novel Aspects of the Chemical Modification of Silica Surface ................................................... ,670 V. Tertykh

Microporous Thermal Insulation: Theory, Properties, Applications ............................................ ,682 H. Katzer, J. Weis

Nitridosilicates - High Temperature Materials with Interesting Properties W. Schnick, H. Huppertz, 7: Schlieper

,691

Contents XV

Author Index .............................................................................................................................. 705

Subject Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . , . , . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 1 1

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List of Contributors

Prof. Dr. Yitzhak Apeloig Department of Chemistry Technion - Israel Institute of Technology Technion City 32000 Haifa Israel

Prof. Dr. Guy Bertrand Laboratoire de Chimie de Coordination du CNRS 205 route de Narbonne F-3 1077 Toulouse Cedex France

Prof. Dr. T. Barton Department of Chemistry Ames Laboratory (U. S. Department of Energy) Iowa State University Ames, Iowa 5001 1 USA Germany

Dr. Uwe Bohme Institut fir Anorganische Chemie Technische Universitat Bergakademie Freiberg Leipziger StraRe 29 D-09596 Freiberg

Prof. Dr. Gerd Becker Institut f i r Anorganische Chemie Universitat Stuttgart Pfaffenwaldring 55 D-70550 Stuttgart Germany

Dr. Joachim Dautel Institut fur Anorganische Chemie Universitat Stuttgart Pfaffenwaldring 55 D-70569 Stuttgart Germany

Prof. Dr. Peter Behrens Institut f i r Anorganische Chemie Ludwigs-Maximilians-Universitat Munchen Fakultat f i r Chemie MeiserstraRe 1 Ruhr-Universitat Bochum D-80333 Munchen UniversitatsstraRe 150 Germany D-44801 Bochum

Matthias Driess Lehrstuhl f i r Anorganische Chemie I

Germany

Dr. Johannes Belzner Institut f i r Organische Chemie Georg-August-Universitat Gottingen TammannstraBe 2 D-37077 Gottingen Germany

Prof. Dr. W.-W. du Mont Institut f i r Anorganische und Analytische Chemie Technische Universitat Braunschweig Hagenring 30 D-38106 Braunschweig Germany

XVIII List of Contributors

Dr. Gordon Fearon Central Research and Development Dow Corning Corporation Midland, MI, 48686-09994 USA

Dr. Lutz H. Gade Institut f i r Anorganische Chemie Universitat Wurzburg Am Hubland D-97074 Wurzburg Germany

Dr. Barbara Gehrhus School of Chemistry and Molecular Sciences University of Sussex Brighton BN1 9QJ United Kingdom

Dr. Jiirgen Granhoff Hiils Silicone GmbH Analytical Department D-01612 Nunchritz Germany

Prof, Dr. Joseph Grobe Anorganisch-Chemisches-Institut Westfalische Wilhelms-Universitat Wilhelm-Klemm-StraBe 8 D-48149 Miinster Germany

Dr. Christa Grogger Institut f i r Anorganische Chemie Technische Universitat Graz Stremayrgasse 16 A-8010 Graz Austria

Dr. B. R. Harkness Dow Corning Asia Ltd Research Center 603 Kishi, Yamakita Kanagawa 258-01 Japan

Priv. Doz. Dr. Karl Hassler Institut f i r Anorganische Chemie Technische Universitat Stremayrgasse 16 A-8010 Graz Austria

Prof. Dr. Joachim Heinicke Institut fur Anorganische Chemie Emst-Moritz-Amdt-Universitat Greifswald SoldtmannstraBe 16 D- 17487 Greifswald Germany

Prof. Dr. Klaus Jurkschat Fachbereich Chemie der Universitat Dortmund Lehrstuhl f i r Anorganische Chemie TI D-4422 1 Dortmund Germany

List of Contributors XIX

Prof. Dr. Peter Jutzi Fakultat fin Chemie Universitat Bielefeld UniversitatsstraBe 25 D-336 15 Bielefeld Germany

Prof. Dr. Wolfgang Kaim Institut f i r Anorganische Chemie Universitat Stuttgart Pfatlenwaldring 5 5 D-70550 Stuttgart Germany

Prof. Dr. Hans Heinz Karsch Anorganisch-Chemisches Institut Technische Universitat Miinchen LichtenbergstraRe 4 D-85747 Garching Germany

Dr. Hans Katzer Wacker-Chemie GmbH Geschatsbereich S-Werk Kempten Max-Schaidhauf-StraBe 25 D-87437 Kempten Germany

Prof. Dr. Hans Kelling Fachbereich Chemie Universitat Rostock BuchbinderstraBe 9

Germany D- 1805 1 Restock

Dip1.-Ing. Alois Kleewein Institut fhr Anorganische Chemie Technische Universitat Graz Stremayrgasse 16 / IV A-8010 Graz Austria

Prof. Dr. Uwe Klingebiel Institut fur Anorganische Chemie Georg- August-Universitat Gottingen TammannstraBe 4 D-37077 Gottingen Germany

Dr. Karl Wilhelm Klinkhammer Institut f i r Anorganische Chemie Universitat Stuttgart Pfaffenwaldring 55 D-70550 Stuttgart Germany

Dr. Michael Knorr Institut f i r Anorganische Chemie Universitat des Saarlandes Postfach 1 150 D-66041 Saarbriicken Germany

Prof. Dr. Daniel Kost Department of Chemistry Ben Gurion University of the Negev Beer-Sheva 84 105 Israel

XX List of Contributors

Dr. F.-H. Kreuzer Consortium fir elektrochemische Industrie GmbH Corporate Research Company of Wacker-Chemie GmbH D-57068 Siegen ZielstatterstraBe 20 Germany

D-8 1379 Munchen Germany

Prof. Dr. Adalbert Maercker Institut f i r Organische Chemie Universitat Siegen

Prof. Dr. Heinrich Lang Institut f i r Chemie Lehrstuhl f%r Anorganische Chemie Technische Universitat Chemnitz StraBe der Nationen 62 D-09107 Chemnitz Germany

Dr. Paul D. Lickiss Department of Chemistry Imperial College of Science Technology and Medicine London SW7 2AY United Kingdom

Prof. Dr. Heiner Lieske Institut fir Angewandte Chemie Berlin- Adlershof e.V. Abteilung Katalyse Rudower Chaussee 5 D- 12484 Berlin Germany

Dr. Gerald Linti Institut fir Anorganische Chemie der Universitat (TH) Karlsruhe Engesserstrane Geb. 30.45 D-76128 Karlsruhe Germany

Prof. Dr. Gunther Maier Institut f i r Organische Chemie Justus-Liebig-Universitat GieBen Heirich-Buff-Ring 58 D-35392 GieBen Germany

Prof. Dr. Wolfgang Malisch Institut fir Anorganische Chemie Universitat Wurzburg Am Hubland D-97074 Wurzburg Germany

Dr. Christoph Marschner Institut f i r Anorganische Chemie Technische Universitat Graz Stremayrgasse 16 A-8010 Graz Austria

Prof. Dr. Heinrich Christian Marsmann Fachbereich Chemie und Chemietechnik Universitat-GH Paderborn Warburger StraBe 100 D-33095 Paderborn Germany

List of Contributors XXI

Prof. Dr. Gerhard Miiller Fakultat f i r Chemie der Universitat Konstanz UniversitatsstraRe 10 Geschaftsbereich S-Werk Burghausen D-78464 Konstanz Johannes-HeB-StraRe 24 Germany D-84489 Burghausen

Dr. B. Pachaly Wacker-Chemie GmbH

Germany

Dr. Thomas Miiller Prof. Dr. Eckhard Popowski Fachinstitut fur Anorganische und Allgemeine Fachbereich Chemie Chemie Universitat Rostock Humboldt-Universitat zu Berlin BuchbinderstraBe 9 Hessische StraBe 1-2 D- 10 1 15 Berlin Germany

D-1805 1 Rostock Germany

Dr. U. Miiller Institut f i r Organische Chemie Martin-Luther-Universitat Halle-Wittenberg Geusaer StraBe D-062 17 Merseburg Germany

Dr. C. Priou Rhone-Poulenc Chimie Silicone Division 1 rue des freres Perret, B.P. 22 F-69 191 Saint Fons cedex France

Christina Notheis Dr. Ralf Riedel Institut f i r Analytische Chemie Technische Universitat Bergakademie Freiberg Leipziger StraRe 29 D-09599 Freiberg PetersenstraRe 23 Germany D-64287 Darmstadt

Fachbereich Materialwissenschaft Fachgebiet Disperse Feststoffe Technische Hochschule Darmstadt

Germany

Prof. Dr. Hartmut Oehme Fachbereich Chemie Abteilung Anorganische Chemie Universitat Rostock BuchbinderstraBe 9

Germany D- 1805 1 Restock

Prof. Dr. Herbert W. Roesky Institut f i r Anorganische Chemie der Universitat Gottingen TammannstraRe 4 D-37077 Gottingen Germany

XXII List of Contributors

Prof. Dr. Gerhard Roewer Institut f ir Anorganische Chemie Technische Universitat Bergakademie Freiberg Leipziger StraBe 29 D-09596 Freiberg Germany

Dr. Klaus Rose Fraunhofer-Institut fiir Silicatforschung Neunerplatz 2 D-97082 Wurzburg Germany

Prof. Dr. Wolfram Sander Lehrstuhl fur Organische Chemie I1 Ruhr-Universitat Bochum D-44780 Bochum Germany

Prof. Dr. Peter Sartori Anorganische Chemie Gerhard Mercator Universitat-Gesamthochschule- Duisburg LotharstraBe 1 D-47048 Duisburg Germany

Prof. Dr. Wolfram Schnabel Hahn-Meitner-Institut Berlin GmbH Bereich Physikalische Chemie Glienicker StraBe 100 D- 14 109 Berlin Germany

Prof. Dr. Wolfgang Schnick Laboratorium f i r Anorganische Chemie Universitat Bayreuth UniversitatsstraBe 30 D-95440 Bayreuth Germany

Prof. Dr. Hans-Ullrich Siehl Abteilung fiir Organische Chemie der Universitat Ulm D-89069 Ulm Germany

Prof. Dr. U. Schubert Institut fur Anorganische Chemie Technische Universitat Wien Getreidemarkt 9 A- 1060 Wien Austria

Dr. Stefan Stadtmuller Th. Goldschmidt AG GoldschmidtstraBe 100 D-45 127 Essen Germany

Prof. Dr. Dietmar Stalke Institut f i r Anorganische Chemie Universitat Wurzburg Am Hubland D-97074 Wurzburg Germany

List of Contributors XXIII

Dr. Karl Stoppek-Langner Anorganisch-Chemisches-Institut Westfalische Wilhelms-Universitat Wilhelm-Klemm-StraBe 8 D-48 149 Munster Germany

Dr. B. Strehmel Fachinstitut fur Physikalische und Theoretische Chemie Humboldt Universitat zu Berlin BunsenstraBe 1 D-10117 Berlin Germany

Priv.-Doz. Dr. Carsten Strohmann Institut f i r Anorganische Chemie Universitat des Saarlandes Postfach 1 150 D-6604 1 Saarbriicken Germany

Dr. Harald Stiiger Institut fur Anorganische Chemie Technische Universitat Graz Stremayrgasse 16 A-8010 Graz Austria

Dr. Matthias Tacke University College Dublin Department of Chemistry Belfield Dublin 4 Ireland

Prof. Dr. Reinhold Tacke Institut fur Anorganische Chemie Bayerische Julius-Maximilians-Universitat zu

Wurzburg Am Hubland D-97074 Wurzburg Germany

Dr. Masaharu Takahashi Silicone-Electronics Materials Research Center Shin-Etsu Chemical Co., Ltd. 1-10, Hitomi, Matsuida Gunma 379-02 Japan

Prof. Dr. Valentin Tertykh Department of Chemisorption Institute of Surface Chemistry National Academy of Sciences Prospekt Nauki 3 1 252022 Kiev Ukraina

Dr. Frank Uhlig Lehrstuhl fur Anorganische Chemie I1 Universitat Dortmund Otto-Hahn-StraBe 6 D-44227 Dortmund Germany

Dr. Wolfram Uhlig Laboratorium f i r Anorganische Chemie Eidgenossische Technische Hochschule Zurich ETH-Zentrum CH-8092 Zurich Switzerland

XXIV List of Contributors

Prof. Dr. Stan Veprek Institut h r Chemie Anorganischer Materialien Technische Universitat Munchen LichtenbergstraBe 4 D-85747 Garching Germany

Dr. R. Wagner Max-Planck-Institut f i r Kolloid-und Grenzflachenforschung Rudower Chaussee 5 D-12489 Berlin Germany

Prof. Dr. Manfred Weidenbruch Fachbereich Chemie Universitat Oldenburg Carl-von-Ossietzky-StraBe 9 D-26111 Oldenburg Germany

Prof. Dr. Matthias Westerhausen Institut f i r Anorganische Chemie Ludwig-Maximilians-Universitat Munchen MeisterstraBe 1 D-80333 Miinchen Germany

Prof. Dr. Nils Wiberg Institut fur Anorganische Chemie Ludwig-Maximilians-Universitat Munchen MeisterstraBe 1 D-80333 Munchen Germany

List of Contributors XXV

Editors:

Prof. Dr. Norbert Auner Fachinstitut f i r Anorganische und AIlgemeine Chemie Geschaftsbereich S Humboldt-Universitat zu Berlin Werk Burghausen Hessische StraBe 1-2 Johannes-Hen-StraBe 24 D-10115 Berlin D-84489 Burghausen Germany Germany

Dr. Johann Weis Wacker-Chemie GmbH

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PART I

FASCINATING ORGANOSILICON COMPOUNDS

INTRODUCTION

Norbert Auner Gordon Fearon Johann Weis Hum boldt- Universitat Dow Corning Corporation Wucker-Chemie GmbH

Berlin, Germany Midland, MI, USA Miinchen, Germany

To understand Group 14 - and especially organosilicon - chemistry some comparisons between silicon and carbon have to be considered. There are two major properties that distinguish silicon from carbon. Silicon atoms are about 50 % larger than carbon atoms and this increased size will have some ramifications and consequences, such as lower barriers to silicon-element bond rotations and less stable n-bonds. Furthermore, the smaller Pauling electronegativity of silicon results in differently polar silicon-element bonds compared to carbon and thus will change its reactivity and enable reactions not possible in carbon chemistry.

rare

The common environments exhibited for carbon and silicon show that silicon differs from carbon by its strongly reduced ability to form multiple bonds in comparison to its congener carbon but also in its capacity to form stable derivatives with more than four bonds. Carbon exhibits a maximum of four single covalent bonds, derivatives with more (e.g. five) nearest neighbors only exist in 'non classical (carbon bridged) ions', in a few carbon gold complexes and in some organometallic carbide compounds. The lack of multiple bonds seriously hampers synthetic strategies in silicon chemistry compared to the numerous possibilities available to the organic chemists. But this lack is counterbalanced by the ease of formation of silicon hypervalent species, the low activation energies

2 N. Auner, G. Fearon, J. Weis

for nucleophilic substitution at silicon compared to carbon and the numerous reaction pathways at tetrahedral silicon centers that are not accessible to carbon.

Although over years a hybridization state has often been used to describe the expanded octet geometries of silicon - this is by no means the exclusive bonding view for higher coordinate species - one has to take into account that the participation of d-orbitals in the description of bonding in silicon compounds was a subject of continuing debate and that nowadays an alternative explanation using multicenter bonding has been accepted.

Besides other organizing principles, compounds of silicon might be ordered in terms of oxidation states and coordination numbers at the silicon centers. Tetravalent silicon mostly exhibits the oxidation state +4 (e.g. ,Six, X = halogen, H, organo group, 5502, Si3N4, Sic etc.), in Ca2Si however it is -4. Divalent silicon in the oxidation state +2 is found in compounds such as :SiX2, SiO or SiS which are available only at high temperatures and can be identified spectroscopically in the gas phase at low pressure andlor in low temperature matrices after condensation on a cold surface (T-1OK ). As examples for tri- and monovalent silicon with positive oxidation numbers +3 and +1 compounds Six3 and Six are named, which are formed competitively to silylenes : Six2 by photolysis and/or thermolysis of stable precursors S i x . Negative oxidation states -3, -2 and -1 with tri-, di-, and monovalent silicon are represented in silicides, as exemplified by BaMgZSiz, CaSi, and CaSi2.

In its compounds the silicon center is surrounded by at least one up to ten neighbors. Some representative specimens in various coordination numbers are listed below and discussed later in this introduction.

10 (CsMe5)zSi: (see page 9)

This list of compounds with silicon in the whole range of its coordination numbers and environments, including their synthesis and the investigation of their chemistry gives an impressive overview of organosilicon research currently going on worldwide.