Modeling Marvels (eBook)

Preface 7
Contents 8
1 Planar Carbon 12
Introduction 12
Dimethanospiro[2.2]octaplane: A Computational Saga 14
Synthesis 20
Conclusions 21
Notes 22
2 Pyramidal Carbon 24
Introduction 24
Pyramidane 25
Other Molecules with Possibly Pyramidal Carbon 35
Synthesis 36
Conclusions 38
Notes 38
3 Oxirene 41
Introduction 41
The Oxirene Problem: History 43
Oxirenes to 1981 Summary
Oxirenes After 1981 49
Synthesis 59
Conclusions 60
Notes 60
4 Nitrogen Pentafluoride and Related Compounds 63
Introduction 63
Nitrogen Pentafluoride, the Octet Rule, and Hypervalency 63
The Predicted Properties of NF5 69
Related Nitrogen Compounds 71
Hypercoordinate Compounds of Other Nonmetals 72
Synthesis 72
Conclusions 73
Notes 74
5 Helium Compounds 76
Introduction 76
Overview of the Chemistry of Neon, Argon, Krypton, Xenon, (Radon) 76
Helium Compounds 80
Synthesis 86
Notes 87
6 Tetrahedrane 90
Introduction 90
Counterfeit Chemistry: A Fictional Synthesis of a Tetrahedrane 91
Real Syntheses of Tetrahedranes 92
Tetra-t-butyltetrahedrane, Synthesis 92
Tetra-t-butyltetrahedrane, Properties 94
Tetrakis(trimethylsilyl)tetrahedrane, Synthesis 96
Tetrakis(trimethylsilyl)tetrahedrane, Properties 96
Tetrahedranyllithium (and Compounds Derived Therefrom) 99
Tetra t-butyltetrahedrane, B3LYP/6-31G* Calculations 103
Tetrakis(trimethylsilyl)tetrahedrane, B3LYP/6-31G* Calculations 103
The Parent Tetrahedrane, Calculations 103
Some Calculated Properties of Tetrahedrane 105
Synthesis 109
Notes 110
7 Orthogonene 114
Introduction 114
Orthogonenes 1 and 4 116
Synthesis 119
Conclusions 121
Notes 121
8 Hexaphenylethane 123
Introduction 123
Hexaphenylethane: The Classical Period 123
Hexaphenylethane: The Modern Period 126
Synthesis 131
A Related Compound 134
Conclusions 136
Notes 136
9 Ethenedione, C2O2 138
Introduction 138
Electronic Structure and Stability of Ethenedione 138
Attempts to make Ethenedione 140
Species Related to Ethenedione 142
Synthesis 144
Conclusions 145
Notes 145
10 Nitrogen Oligomers and Polymers: Superfuels or Chimeras? 148
Introduction 148
Experimental Results 149
Theoretical Results 155
Cyclic N8 Molecules 155
Cyclic N6 Molecules 155
Cyclic N4 Molecules 162
Cyclic Polynitrogens with Several Rings 163
Acyclic Molecules 163
Some "Conventional" Polynitrogens 164
Synthesis 166
Conclusions 166
Notes 167
11 Oligomers and Polymers of Carbon Dioxide and CO2/N2 171
Introduction 171
CO2 Compounds 171
CO2--N2 Compounds 177
Structures (B3LYP/6-31G--) of the CO2--N2 Compounds (Fig. 11.5) 181
Decomposition Reactions (B3LYP/6-31G-- and MP2/6-31G--) of the Cyclic CO2--N2 Compounds (Fig. 11.6) 181
The B3LYP/6-31G* Reaction Profiles (Fig. 11.6) 181
The MP2/6-31G* Reaction Profiles (Fig. 11.7) 184
Stability of the Acyclic CO2--N2 Compounds 13a, 13b, 13c 184
Synthesis 186
The CO2 Compounds 186
The CO2 N2 Compounds 186
Summary 188
The CO2 Dimer etc., Stability 188
The CO2--N2 Dimer etc., Stability 189
Synthesis 189
Notes 189
12 Polyprismanes. Flights of Fun and Fancy 191
Introduction 191
Simple Prismanes 193
Polyprismanes 198
Some Computed Properties of Polyprismanes 207
Strain 208
Thermodynamic Stability 210
Kinetic Stability 215
Two Simple Reactions: Attack by a Hydride Ion and by a Proton 219
Other Candidates for Half-Planar or Linear C--C--C Carbons 224
Some Other Rodlike Molecules: Carbon Nanotubes, Staffanes, Ladderanes 226
Polyprismanes: Synthesis 228
Conclusions 230
Notes 230
13 A Menagerie of Molecules from Michl and Balaji: Superstrained Molecules 233
Introduction 233
Molecules 1, 2, and 3 (Known Species) 233
Molecules 4, 5, 6, 7 (Unknown Species) 241
A Comparative Survey of some Salient Characteristics of 1--7: Geometry, Strain, Ionization Energies, and IR and Electronic Spectra 249
Synthesis 255
Conclusions 259
Notes 259
14 Summary 263
Introduction 263
Our Medley of Molecules, Arranged by Common Themes 264
Metamedley 276
Notes 278
Index 280