Files
Abstract
The syntheses and molecular structures of several organometallic group 13 compounds and complexes are presented herein. The organometallic chemistry of RLi (R = 2,6-(4-t-BuC6H4)2C6H3-) and RLi (R = 2,6-(4-Me-C6H4)2C6H3-) was examined on group 13 halides to yield a number of new compounds 1-8: RGaCl2(OEt2) (1), R2GaCl (2), RAlBr2(OEt2) (3), [RAlCl(OEt2)]2O (4), R3In (5), [RGaCl3][Li(OEt2)2] (6), [RInCl3][Li(OEt2)(THF)] (7), R3In. Compounds 5 and 8 are notable as the first tris-m-terphenyl-group 13 compounds, while 4 is an interesting oxo-bridged-di(m-terphenyl-aluminum chloride) complex with exceptionally long AlCl bonds. Sodium metal reduction of 1 provides a rare catenated tri-gallium complex, [R3Ga3][Na(OEt2)]3 (9).Additionally, the organometallic chemistry at the group 13group 4 interface was explored, wherein three new compounds were isolated: Cp2Hf(ER)2 (10, E = Ga; 11, E = In; R = 2,6-(2,4,6-i-Pr3C6H2)2C6H3-) and (C10H8)(ZrCp)2(H)(Cl)(GaR) (R = 2,6-(4-t-BuC6H4)2C6H3-) (12). Compounds 10 and 11 contain the first reported group 13Hf bonds, while compound 12 is the only compound with gallium engaged in bonding with two zirconium atoms. Extending the organometallic chemistry of m-terphenyl ligands to the group 4 metallocenes gave the first m-terphenyltitanium(III) radical Cp2TiR (13) and the first m-terphenylzirconocene(IV) compound, Cp2ZrR(Cl) (14) (R = 2,6-(4-t-BuC6H4)2C6H3-). This research project also involved the study of heterometallic aromaticity, which ultimately produced the first gallepin, bis(gallepin)2TMEDA (18), by the reaction of 2,2-dilithio-Z-stilbene(TMEDA)2 (16) and GaCl3. The aromatic nature of the gallepin was evaluated using Nucleus-Independent Chemical Shifts (NICS) and compared to that of borepins.Additionally, the -donor properties of N-heterocyclic carbenes were evaluated on mesityl-group 13 dihalides, wherein several new carbene-mesityl-group 13 dihalide adducts were prepared: MesGaCl2(:L) (19), MesAlBr2(:L) (20), MesInBr2(:L) (21) (Mes = 2,4,6-Me3C6H2-; :L = :C 2). Potassium graphite reduction of 19 yielded a rare meso-digallane, [MesGaCl(:L)]2 (22), with four-coordinate gallium atoms, while reduction with potassium metal unexpectedly produced an unprecedented neutral Ga6-octahedron cluster, Mes4Ga6(:L)2 (23). NICS calculations were used to support its aromatic properties and compared with that of the thoroughly studied dianionic hexaborate octahedron, [B6H6]-2.In conjunction with these studies a new detailed synthetic protocol to prepare Arduengos carbene (26) from adamantylammonium chloride was established and full single crystal X-ray structural analysis reported.