Carbosilanes

I. Introduction.- 1. Characteristic Differences between the Elements Silicon and Carbon.- 2. Functional Groups in the Chemistry of Silicon.- II. The Formation of Carbosilanes.- 1. The Formation of Carbosilanes by Thermal Decomposition of Methylsilanes.- 1.1 The Homolytic Cleavage of Silanes.- 1.2 Continous Flow Pyrolysis.- 1.3 The Thermal Decomposition of SiMe4.- 1.3.1 The Separation of Pyrolysis Products.- 1.3.2 Compounds of Low Boiling Point Containing up to Four Si Atoms.- 1.3.3 Compounds with Polycyclic Molecular Structures.- 1.3.4 Influence of Distillation Temperature on the Composition of the Pyrolysis Products.- 1.4 Formation of Si-Chlorinated Carbosilanes by Pyrolysis of Methylchlorosilanes.- 1.5 Pyrolysis of the Methylsilanes Me3SiH, Me2SiH2 and MeSiH3.- 1.6 Reactions of Methylsilanes by Gas Discharge.- 1.6.1 Reactions of SiMe4, Me2SiH2 and MeSiH3.- 1.6.2 Comparison of the Products Obtained from Reactions in Cold Plasma with those from Pyrolysis.- 1.7 Mechanism of the Formation of Carbosilanes by Pyrolysis in the Gas Phase.- 1.7.1 The Mechanism of Formation via Radical Reactions.- 1.7.2 Insertion of CH2 Groups into Si-Si Bonds.- 1.7.3 Participation of Volatile Cyclic Compounds in the Pyrolysis Reaction.- 1.7.4 Comments on the Formation of SiCl-Containing Carbosilanes from Methylchlorosilanes.- 1.7.5 Pyrolysis Products Obtained from EtSiCl3 in Comparison to those from Me2SiCl2.- 1.8 Comparative Summary of the Carbosilanes Synthesized.- 1.9 A Possible Chemical Pathway to the Synthesis of Polycyclic Molecular Skeletons.- 2. Formation of Carbosilanes by Direct Reaction of Halogenomethanes with Silicon.- 2.1 Reactions of Silicon with Chloromethanes.- 2.1.1 The Reaction with CH2Cl2.- 2.1.2 The Reaction with CHCl3.- 2.1.3 The Reaction with CCl4.- 2.2 Advantages Associated with Forming Carbosilanes in a Fluid Bed.- 2.3 Comments on Mechanism of Formation.- 2.4 The Reaction with (Cl3Si)2CCl2.- 3. Formation of Polycyclic Molecular Skeletons through Rearrangement of Carbosilanes with AlBr3 or AlCl3.- 3.1 Introduction.- 3.2 The Reactions of Structurally Different Carbosilanes.- 3.2.1 The Effect of the Length of Skeletal C-Bonded Side Chains on Ring Formation.- 3.2.2 Reactions of Carbosilanes Containing Side Chains Bonded to Si-Atoms in the Molecular Skeleton.- 3.2.3 Ring Closure by Elimination of Methane.- 3.2.4 Rearrangements Leading to the Formation of Larger Scaphanes or Carborundanes.- 3.2.5 Rearrangement of Larger Rings.- 3.3 Investigation into Ring Closure Reactions During Rearrangement Reactions of Carbosilanes.- 3.4 Investigations into the Stability of Carbosilane Skeletons Towards AlBr3 and AlCl3.- 3.4.1 The Formation of CH2-Linked 1,3,5,7-Tetrasilaadamantanes.- 3.4.2 Reactions of 1,3,5,7-Tetrasilaadamantanes with AlCl3.- 3.4.3 The Behavior of Heptasiladiadamantanes Towards AlBr3.- 3.4.4 The Behavior of Tetrasilatriscaphanes Towards AlBr3.- 3.4.5 The Effect of the Lewis Acids BCl3, PCl3 and SbCl3 on Unstrained Carbosilanes.- 3.4.6 The Behavior of Si-Halogenated Carbosilanes Towards AlBr3.- 3.4.7 Summary.- 4. Organometallic Syntheses of Carbosilanes.- 4.1 SiPh Groups as Important Protecting Groups in the Organometallic Synthesis of Carbosilanes.- 4.1.1 Synthesis of Pentasiladecalin.- 4.1.2 Synthesis of Hexasilaperhydrophenalene.- 4.1.3 Synthesis of Heptasila[4.4.4]propellane.- 4.2 Investigations into the Synthesis of Tetrasilaadamantanes.- 4.2.1 Investigations of 1,3,5-Trisilacyclohexanes.- 4.2.1.1 Synthesis of (t-BuHSi-CH2)3.- 4.2.1.2 Synthesis of (PhHSi-CH2)3.- 4.2.1.3 Formation of (RBrSi-CH2)3 through Bromination.- 4.2.1.4 Synthesis of (PhHSi-CH2)3 via (Ph2Si-CH2)3.- 4.2.1.5 The Cleavage of Si-Ph Bonds in (Ph2Si-CH2)3.- 4.2.2 Attempts to Synthesize Tetrasilaadamantanes.- 4.3 Synthesis of Si-Substituted 1,3,5,7-Tetrasilaadamantane Me3(Me3Si-CH2-SiMe2-CH2-SiMe2-CH2)Ad.- 4.4 Synthesis of C-Bridged Cyclic Carbosilanes.- 4.4.1 Syntheses via Metallation of CBr2 Groups.- 4.4.1.1 C-Metallation and Reactions of 2,2-Dibromo-1,1,3,3,5,5-hexamethyl-1,3,5-trisilacyclohexane.- 4.4.1.2 Synthesis of C-Bridged Spiro Carbosilanes.- 4.4.2 Syntheses via Metallation of CH2 or CH Groups.- 4.4.2.1 Synthesis of Me4Ad(-SiMe2-CH2-SiMe2Ph) and of Me4Ad(-SiMe2-CH2-SiMe2-CH2-SiMe3).- 4.4.2.2 Synthesis of (Me3Si)2CH-SiMe2-CH2-SiMe2-CH2-SiMe3.- 4.4.2.3 Synthesis of (Me3Si)2CH-SiMe(CH2-SiMe2-CH2-SiMe3)2.- 4.4.2.4 Synthesis of (Me3Si)3C-SiMe2-CH2-SiMe2-CH2-SiMe3.- 4.4.3 Synthesis of C-Substituted Carbosilanes through Metallation of CH2 or CH Groups.- 4.4.3.1 2-Trimethylsilyl-2-dimethyl(phenyl)silyl-1,1,3,3,5,5-hexamethyl-1,3,5-trisilacyclohexane and 2,2-Bis(trimethylsilyl)-1,1,3,3,5,5-hexamethyl-1,3,5-trisilacyclohexane.- 4.4.3.2 Synthesis of C-Silylated 6-Trimethylsilyl-1,3,5,7,9-pentasiladecalin.- 4.4.3.3 Synthesis of C-Bridgehead Silylated Tetrasilatriscaphanes.- 4.5 Synthesis of 1,3-Disilapropanes.- 4.5.1 Synthesis of 2,2-Dichloro-1,3-disilapropanes.- 4.5.2 Synthesis of 2-Methyl-2-chloro-1,3-disilapropanes.- III. Reactions of Carbosilanes.- 1. Introduction.- 2. The Introduction of New Functional Groups on the Carbosilane Molecular Skeleton.- 2.1 C-Halogenation of Carbosilanes.- 2.1.1 C-Chlorinated Carbosilanes.- 2.1.2 C-Brominated Carbosilanes.- 2.1.3 Photobromination of Si-Methylated Carbosilanes.- 2.2 Formation and Reactions of Si-Hydrogenated Carbosilanes.- 2.2.1 Hydrogenation of SiCl- and CH-Containing Carbosilanes.- 2.2.2 SiH-Bromination of Carbosilanes.- 2.2.2.1 (H3Si)2CH2.- 2.2.2.2 (H3Si-CH2)2SiH2.- 2.2.2.3 (H2Si-CH2)3.- 2.2.3 C-Chlorinated, SiH-Containing Carbosilanes.- 2.2.4 Reaction of (Cl3Si)2CBr2 with LiAlH4.- 2.2.5 Partly C-Chlorinated, SiH-Containing Carbosilanes.- 2.2.6 Reactions of Perchlorinated Carbosilanes with Perhydrogenated Carbosilanes.- 2.3 Si-Fluorinated Carbosilanes.- 2.3.1 Fluorination of SiCl-Containing Carbosilanes.- 2.3.2 Cyclic Carbosilanes Containing SiF and CCl Groups.- 2.3.3 Partly C-Halogenated, Si-Fluorinated Carbosilanes.- 3. Reactions with MeMgCl and MeLi.- 3.1 SiH-Containing Carbosilanes.- 3.1.1 Reactions of (H3Si-CH2)2SiH2 and (H2Si-CH2)3.- 3.1.2 Linear CCl-, SiH-Containing Carbosilanes.- 3.1.3 (H3Si)2CHCl, H3Si-CClH2, H3Si-CCl2H and H3Si-CCl3.- 3.1.4 H3Si-CCl2-SiH2-CH2-SiH3.- 3.1.5 (H3Si-CCl2)2SiH2.- 3.2 Si- and C-Chlorinated Carbosilanes.- 3.2.1 Reaction of (Cl3Si)2CCl2.- 3.2.2 Mechanism of Formation of Methylidene Groups.- 3.2.2.1 (Me3Si)2CMeCl.- 3.2.2.2 Varying Si-Chlorinated 2-Methyl-2-chloro-1,3-disilapropanes.- 3.2.2.3 Reactions of 2,2-Dichloro-1,3-disilapropanes.- 3.2.3 Reaction Pathways Taken by (Cl3Si)2CCl2.- 3.2.4 Reactions of 1,3,5-Trisilapentanes.- 3.2.4.1 (Cl3Si-CCl2)2SiCl2 and MeMgCl.- 3.2.4.2 (Cl3Si-CCl2)2SiCl2 and MeLi.- 3.3 Reactions of 1,3,5-Trisilacyclohexanes.- 3.3.1 Reactions of (Cl2Si-CCl2)3 with MeMgCl.- 3.3.2 Reactions of Partly Chlorinated 1,3,5-Trisilacyclohexanes with MeMgCl.- 3.3.3 Si-Hydrogenated 1,3,5-Trisilacyclohexanes.- 3.3.4 Reactions of Si-Methylated, Partly C-Brominated 1,3,5-Trisilacyclohexanes wit BuLi and EtMgBr.- 3.3.5 Consideration of Chemical Behavior and NMR Chemical Shift of 1,3,5-Trisilacyclohexanes.- 3.4 SiF-, CCl-Containing Carbosilanes.- 3.4.1 (F3Si)2CCl2.- 3.4.2 F3Si-CCl2-SiF2-CH2-SiF3 and F3Si-CCl2-SiF2-CHCl-SiF3.- 3.4.3 (F3Si-CCl2)2SiF2.- 3.4.4 Reactions of Si-Fluorinated 1,3,5-Trisilacyclohexanes.- 3.4.4.1 Reactions with MeMgCl and MeLi.- 3.4.4.2 Reactions with Phenyllithium and PhMgBr.- 3.4.5 Summary of the Behavior of SiH- and SiF-Containing C-Chlorinated Carbosilanes.- 3.4.6 CF2-Containing 1,3-Disilapropanes.- 3.4.6.1 Formation of Si-CF2-Si Groups by Insertion of a CF2 Carbene into the Si-Si Bond.- 3.4.6.2 Reactions of CF2-Containing Carbosilanes.- 4. Metallation of Carbosilanes.- 4.1 Metallation of Skeletal C-Atoms in Si-Methylated Carbosilanes.- 4.1.1 (Me2Si-CH2)3.- 4.1.2 Me4Ad.- 4.1.3 Summary.- 4.2 Metallation of Bridging C Atoms in CCl- and SiCl-Containing 1,3-Disilapropanes.- 4.2.1 Evidence of CCl2-Lithiation in the Presence of SiCl Groups.- 4.2.2 Metallation of Me3Si-CCl2-SiMe2Cl.- 4.2.3 Formation of 2,2,4,4-Tetramethyl-1,3-bis(trimethylsilyl)-2,4-disilabicyclo[1.1.0]butane.- 4.2.4 The Reactive Behavior of 2,2,4,4-Tetramethyl-1,3-bis(trimethylsilyl)-2,4-disilabicyclo[1.1.0]butane.- 4.2.5 Lithiation of Me3Si-CCl2-SiMeCl2.- 4.3 The Si-Metallation of 1,3,5-Trisilacyclohexanes with Transition Metal Complexes.- 4.3.1 Si-Metallation via Salt Elimination.- 4.3.1.1 Singly Metallated Trisilacyclohexanes.- 4.3.1.2 Doubly Metallated Trisilacyclohexanes.- 4.3.1.3 Triply Metallated Trisilacyclohexanes.- 4.3.1.4 Reaction of (Cl2Si-CH2)3 with KFe(CO)2cp.- 4.3.2 Cobalt-Substituted 1,3,5-Trisilacyclohexane Complexes.- 4.3.2.1 Multiply Cobalt-Carbonylate-Substituted Trisilacyclohexanes.- 4.3.2.2 Reactions of (H2Si-CH2)3 with Co2(CO)8.- 4.3.3 Influence of cp(CO)2Fe Groups on the Reactive Behavior of Trisilacyclohexanes.- 5. Reactions of C-Chlorinated Carbosilanes with Silylphosphanes.- 5.1 Formation and Reactions of the Ylide (Cl3Si)2CPMe2Cl and the Effect of Substituents on Ylide Formation.- 5.2 The Triylide (Cl2Si-CPMe2Cl)3.- 5.3 Influence of Si-Substitution on the Formation, Structure and Rearrangement of Ylides.- 6. The Reactive Behavior of Further Cyclic Carbosilanes.- 6.1 1,3-Disilacyclobutanes.- 6.2 1,3-Disilacyclobutane Rings in Hexasilaasteranes.- 6.3 1,3-Disilacyclopentenes.- 6.3.1 Tetramethyl-1,3-disilacyclopentenes.- 6.3.2 4-Trimethylsilyl-tetramethyl-1,3-disilacyclopentene.- 6.4 Tetrachloro-l,3-disilacyclopentane.- 6.4.1 Stepwise Photochlorination.- 6.4.2 Reaction of 1,3-Disilacyclopentanes with MeMgCl.- 6.5 Tetrasilabicyclo[3.3.0]oct-1(5)ene.- 7. Investigations into the Cleavage of Si -Me Bonds in Carbosilanes.- 7.1 Si-Chlorination of (Me2Si-CH2)3 with HSiCl3/H2PtCl6.- 7.2 Cleavage with ICl.- 7.2.1 Hexamethyl-1,3,5-trisilacyclohexane.- 7.2.2 Linear Carbosilanes.- 7.2.3 1,3,5-Trisilacyclohexanes with Side Chains.- 7.2.4 Adamantanes.- 7.2.5 Adamantanes with Side Chains.- 8. Substituent Effects in Carbosilanes.- 9. Hydrosilylation in Carbosilane Chemistry.- 9.1 Formation of Cyclic Carbosilanes Through Hydrosilylation.- 9.2 Linking of Linear SiH-Containing Carbosilane Units Over HC ? CH.- IV. Results of Structural Investigations of Carbosilanes.- 1. X-Ray Investigations of Crystal Structures.- 1.1 1,3,5-Trisilacyclohexanes with Different Substituents.- 1.1.1 (Cl2Si-CH2)3 and (Cl2Si-CH2)3.- 1.1.2 (Ph2Si-CH2)3.- 1.1.3 1-Cyclopentadienyl dicarbonyl-iron-1,3,3,5,5-pentachloro-1,3,5-trisilacyclohexane and 1,3-Bis(cyclopentadienyldicarbonyl-iron)-1,3,5,5-tetrachloro-1,3,5-trisilacyclohexane.- 1.1.4 The Ylides (Cl3Si)2CPMe2Cl, (Cl3Si)2CPMe3 and (Cl2Si-CPMe2Cl)3, as well as Cl2Si(CH2-SiCl2)2CPMe2Cl and Me2Si(CH2-SiMe2)2PMe2Br.- 1.2 Structures of Si-Adamantanes.- 1.2.1 1,3,5,7-Tetrasilaadamantane, Si4C10H24.- 1.2.2 Hexamethyl-heptasila-hexacyclo-heptadecane, Si7C16H36.- 1.2.3 Octamethyl-octasila-heptacyclo-octadecane, Si8C18H40.- 1.3 Structures of Si-Scaphanes.- 1.3.1 Heptamethyl-tetrasila[2.2.2]barrelane, Si4C11H28.- 1.3.2 Octamethyl-hexasila-hexascaphane, Si6C15H36.- 1.3.3 Tetramethyl-octasila-dodecascaphane, Si8C17H36.- 1.4 Dodecamethyl-heptasila[4.4.4]propellane, Si7C19H48.- 1.5 trans-trans-1,3,3,5,7,7,9,11,11-Nonamethyl-l,3,5,7,9,11-hexasilatricyclo[7.3.1.05,13]tridecane, Si6C16H36.- 1.6 Structures of Carbosilanes with Small Rings.- 1.6.1 Hexadecamethyl-octasila-dispiro[5.1.5.1]tetradecane, Si8C22H56.- 1.6.2 cis-2,4-Dichloro-2,4-bis(trimethylsilyl)-1,1,3,3-tetramethyl-1,3-disilacyclobutane, Si4C12H30Cl2.- 1.6.3 2,2,4,4-Tetramethyl-1,3-bis(trimethylsilyl)-2,4-disilabicyclo[1. 1.0]butane, Si4C12H30.- 1.6.4 Octachloro-hexasila-asterane, Si6C6H8Cl8.- 1.6.5 Tetrasilabicyclo[3.3.0]oct-l(5)ene, Si4C12H28.- 1.7 Octamethyl-tetrasila-cyclooctane, Si5C12H32.- 2. Electron Diffraction Studies.- V. References.