Organometallic compounds of low-coordinate Si, Ge, Sn, and Pb : from phantom species to stable compounds / Vladimir Ya. Lee and Akira Sekiguchi

Includes bibliographical references and index

Contents Preface Abbreviations 1 Heavy Analogs of Carbenium Ions: Si-, Ge-, Sn- and Pb-Centered Cations 1.1 Introduction 1.2 Synthesis of RR'R"E+ Cations (E = Si-Pb) 1.2.1 From Halides RR'R"EX 1.2.2 From Hydrides RR'R"EH 1.2.3 From RR'R"E-R" and RR'R"E-ERR'R" 1.2.4 From Heavy Carbene Analogs RR'E 1.2.5 From Free Radicals RR'R"E 1.3 Reactions and Synthetic Applications of RR'R"E+ Cations16 1.4 Theoretical Studies 1.4.1 Structure of Cations 1.4.2 Stability of Cations 1.4.3 Calculation of the NMR Chemical Shift of Cations 1.4.3.1 29Si NMR Chemical Shift Calculations 1.4.3.2 119Sn NMR Chemical Shift Calculations 1.5 Early Studies of RR'R"E+ Cations: Free or Coordinated? 1.6 Stable RR'R"E+ Cations 1.6.1 Intramolecularly Stabilized (Coordinated) Cations 1.6.2 Free (Noncoordinated) Cations 1.6.2.1 Cyclic π-Conjugated Cations 1.6.2.2 Acyclic Cations Lacking π-Conjugation 90 1.7 Summary and Outlook 1.8 References 2 Heavy Analogs of Organic Free Radicals: Si-, Ge-, Sn-and Pb-Centered Radicals 2.1 Introduction 2.2 Early Studies: Transient Species RR'R"E 2.2.1 Generation 2.2.2 Structure (Identification) 2.2.2.1 Electronic Spectroscopy 2.2.2.2 EPR and CIDNP Spectroscopy 2.2.2.2.1 EPR Spectroscopy 2.2.2.3 Theoretical Calculations 2.2.3 Synthetic Applications 2.3 Persistent Radicals (Generation and Identification) 2.4 Stable Radicals 2.4.1 Neutral Radicals 2.4.1.1 Cyclic Radicals 2.4.1.2 Acyclic Tricoordinate Radicals 2.4.2 Charged Radicals 2.4.2.1 Anion-radicals 2.4.2.1.1 Cyclic Anion-radicals 2.4.2.1.2 Acyclic Anion-radicals 2.4.2.1.2.1 Heavy Carbenes Anion-radicals 2.4.2.1.2.2 Heavy Alkenes Anion-radicals 2.4.2.1.2.3 Heavy Alkynes Anion-radicals 2.4.2.2 Cation-radicals 2.4.3 Stable Biradicals of the Heavy Group 14 Elements 2.5 Summary and Outlook 2.6 References 3 Heavy Analogs of Carbanions: Si-, Ge-, Sn-and Pb-Centered Anions 3.1 Introduction 3.2 Synthesis 3.2.1 Alkyl-substituted Silyl Anions 3.2.2 Aryl-substituted Silyl Anions 3.2.3 Silyl-substituted Silyl Anions 3.2.4 Silyl Anions with Functional Groups 3.2.4.1 (Hydrido)Silyllithium Derivatives 3.2.4.2 (Halo)Silyllithium Derivatives 3.2.4.3 (Amino)Silyllithium Derivatives 3.2.4.4 (Alkoxy)Silyllithium Derivatives 3.2.4.5 (Acyl)Silyllithium Derivatives (Lithium Sila-enolates) 3.2.5 Cyclic Anions 3.2.5.1 Silole, Germole and Stannole Anions and Dianions 3.2.5.2 Cyclic Oligosilyl Anions 3.2.6 Polylithiosilanes 3.2.6.1 Tetralithiosilane 3.2.6.2 1, 1-Dilithiosilane Derivatives 3.2.6.3 1, 2-Dilithiodisilane Derivatives 3.2.6.4 1, 3-Dilithiotrisilane and 1, 4-Dilithiotetrasilane Derivatives 3.3.7 Germyl, Stannl and Plumbyl Anions 3.3 Structure 3.3.1 NMR Spectroscopy (Condensed Phase Structure) 3.3.2 X-ray Crystallography (Crystal Structure) 3.4 Reactions and Synthetic Applications 3.5 Recent Developments 3.5.1 sp3 Anions 3.5.2 sp2 Anions 3.5.3 Cyclic and Polycyclic Anions 3.6 Summary and Outlook 3.7 References 4 Heavy Analogs of Carbenes: Silylenes, Germylenes, Stannylenes and Plumbylenes 4.1 Introduction 4.2 Generation 4.2.1 Photolysis of Acyclic Oligo-and Polymetallanes 4.2.2 Photolysis of Cyclic Metallanes 4.2.3 Thermolysis of Oligo-and Monometallanes 4.2.4 α-Elimination of Silylenoids 4.2.5 Heavy Alkene-Heavy Carbene Rearrangements 4.3 Spectroscopic Identification 4.4 Structure 4.4.1 Multiplicity: Singlet vs Triplet 4.4.2 Substituent Effects 4.5 Reactions of Transient Species 4.5.1 Insertion into Single Bonds 4.5.2 Addition to Multiple Bonds 4.5.2.1 Addition to Alkenes 4.5.2.2 Addition to Alkynes 4.5.2.3 Addition to 1, 3-Dienes 4.5.3 Disilenes/Silenes from Silylenes: Dimerization, Rearrangement 4.5.4 Complexation to Transition Metals 4.6 Stable/Persistent Silylenes, Germylenes, Stannylenes and Plumbylenes 4.6.1 Singlet Species 4.6.1.1 Silylenes 4.6.1.2 Germylenes 4.6.1.3 Stannylenes 4.6.1.4 Plumbylenes 4.6.2 Triplet Species: Generation and Identification 4.7 Summary and Outlook 4.8 References 5 Heavy Analogs of Alkenes, 1, 3-Dienes, Allenes and Alkynes: Multiply Bonded Derivatives of Si, Ge, Sn and Pb 5.1 Introduction 5.2 Early Studies: Generation and Identification 5.3 Stable Derivatives (Synthesis and Structure) 5.3.1 Heavy Analogs of Alkenes (including cyclic compounds) 5.3.1.1 Homonuclear Compounds 5.3.1.1.1 Disilenes >Si=Si<3c-e, 12 5.3.1.1.2 Digermenes>Ge=Ge<5c, 71 5.3.1.1.3 Distannenes>Sn=Sn<5c, 71b, d 5.3.1.1.4 Diplumbenes>Pb=Pb<5c, 71d 5.3.1.2 Heteonuclear Compounds 5.3.1.2.1 Group 14/Group 14 Combinations: >E14 = E14'< (E14, E14' = C, Si, Ge, Sn, Pb) 5.3.1.2.1.1 Silenes>Si=C<124 5.3.1.2.1.2 Germenes >Ge=C<71a, c, 124f, i 5.3.1.2.1.3 Stannenes >Sn=C<71b, 124f, i 5.3.1.2.1.4 Plumbenes >Pb=C<5a 5.3.1.2.1.5 Silagermenes >Si=Ge<124i 5.3.1.2.1.6 Silastannes >Si=Sn<124i 5.3.1.2.1.7 Germastannenes >Ge=Sn<124i 5.3.1.2.2 Group 14/Group 13 Combinations: >E14 = E13- (E14 = Si, Ge; E13 = B, Ga, In) 5.3.1.2.3 Group 14/Group 15 Combinations: <E14 = E15- (E14 = Si, Ge, Sn; E15 = N, P, As) 5.3.1.2.3.1 Silaimines >Si=N-179 5.3.1.2.3.2 Germaimines >Ge=N-71a, c, 191a, b 5.3.1.2.3.3 Stannaimines >Sn=N-71b, 191a 5.3.1.2.3.4 Phosphasilenes >Si=P-203 5.3.1.2.3.5 Phosphagermenes >Ge=P-71a-c, 191a 5.3.1.2.3.6 Phosphastannenes >Sn=P-71b, 191a 5.3.1.2.3.7 Arsasilenes >Si=As-217 5.3.1.2.4 Group 14/Group 16 Combinations >E14 = E16 (E14 = Si, Ge, Sn; E16 = O, S, Se, Te) 5.3.1.2.4.1 >E14=O Combinations 5.3.1.2.4.2 >E14=S Combinations 5.3.1.2.4.3 >E14=Se Combinations 5.3.1.2.4.4 >E14=Te Combinations 5.3.2 Heavy Analogs of 1, 3-Dienes and Allenes 5.3.2.1 Heavy Analogs of 1, 3-Dienes 237 5.3.2.2 Heavy Analogs of Allenes245 5.3.3 Heavy Analogs of Alkynes: Disilynes, Digermynes, Distannynes, Diplumbynes, and their Valence Isomers260 5.3.3.1 Disilynes RSiSiR 5.3.3.2 Digermynes RGeGeR (and their Valence Isomers) 5.3.3.3 Valence Isomers of Distannynes RSnSnR 5.3.3.4 Valence Isomers of Diplumbynes RpbPbR 5.3.3.5 Heavy Analogs of Alkynes: Structure and Bonding 5.4 Summary and Outlook 5.5 References 6 Heavy Analogs of Aromatic Compounds 6.1 Introduction 6.2 Early Studies 6.2.1 Transient Species: Generation, Identification and Trapping 6.3 Stable Compounds (Synthesis and Structure) 6.3.1 2π-Electron Species 6.3.1.1 Cyclopropenylium Ion Derivatives 6.3.1.2 Cyclobutadiene Dication Derivatives 6.3.2 6π-Electron Species 6.3.2.1 Benzene (and its Homologs) Derivatives 6.3.2.1.1 Theoretical Studies 6.3.2.1.2 Experimental Accomplishments 6.3.2.2 Cyclopentadienide Ion Derivatives 6.3.2.3 Cyclobutadiene Dianion Derivatives 6.3.2.4 Cycloheptatrienylium (Tropylium) Ion Derivatives 6.3.3 Homoaromaticity 6.3.4 Antiaromaticity 6.3.4.1 Cyclobutadiene Derivatives 6.3.4.2 Cyclopropenyl Anion Derivatives 6.3.4.3 Cyclopentadienylium Ion Derivatives 6.3.5 Reactivity of Heavy Aromatics: Complexation to Transition Metals 6.4 Summary and Outlook 6.5 References Index