Bis(imino)phenyl group 13 - 14 complexes

• Main Author: Seow, Celestine Su Yi
• Other Authors: So Cheuk Wai
• Format: Theses and Dissertations
• Language: English
• Published: 2018
• Subjects: DRNTU::Science::Chemistry::Inorganic chemistry
• Online Access: http://hdl.handle.net/10356/73197
• Institution: Nanyang Technological University

This thesis mainly describes the synthesis and reactivity of group 13 and group 14 complexes stabilized by bis(imino)phenyl ligands. Chapter 1 describes the synthesis and characterization of indium and thallium compounds supported by bis(imino)aryl pincer ligands with Ar* (Ar* = 4-Me-2,6-CHPh2-C6H2) and tBu substituents. The reaction of bis(imino)aryl pincer ligand with Ar* bulky substituents and group 13 metal(I) bromide in toluene or THF led to the formation of a new metal(II) radical, [LAr*(Br)M] (LAr* = C6H3-2,6-(HC=NAr*)2; M = In (1.4) or Tl (1.5)). However, the reaction of bis(imino)phenyl pincer ligand with tBu substituents and indium(I) bromide in toluene afforded a separated ion pair of bis(imino)phenylindium(III) bromide complex, [LtBu2In]Br (1.1, LtBu = C6H3-2,6-(HC=NtBu)2). When the reaction was done in Et2O, an indium(I) trimer, [(LtBuInCl)2LtBuIn] (1.3) was afforded. In addition, the consecutive reaction of LtBuBr, nBuLi and indium(III) chloride afforded a bis(imino)phenylindium(II) dimer, [LtBuInCl]2 (1.2). Chapter 2 describes the synthesis and characterization of a 2,6-bis(imino)phenylchlorogermylene [LtBuGeCl] (2.1, LtBu = C6H3-2,6-(HC=NtBu)2), and its reduction to afford a bis(germylene) [2-(HC–NtBu)-6-(HC=NtBu)C6H3Ge:]2 (2.2) and germylidenide anion [LtBuGeLi]2 (2.3). The reaction of the 2,6-bis(imino)phenyl bromide, LtBuBr with nBuLi in THF at −78 °C, followed by addition to GeCl2·dioxane, afforded 2.1. The reaction of 2.1 with lithium proceeded through a new reaction pathway, involving the reduction of the germanium(II) centers in 2.2, concomitant with the homolytic cleavage of the C–C bond to afford 2.3. Chapter 3 describes the reactivity of [LtBuGeCl] (3.1, LtBu = C6H3-2,6-(HC=NtBu)2) towards group 11 metals. The reaction of 3.1 and AgOTf (OTf = CF3SO3–) in toluene afforded a germylene-silver(I) complex, [{LtBu(TfO)Ge}2Ag(OTf)] (3.2). Further reaction of 3.2 and 1,3-dimethyl-4,5-dimethylimidazol-2-ylidene (IMe) in toluene afforded a bis(germyliumylidene cation)-silver(I) complex, [{LtBu(IMe)Ge}2Ag(OTf)]OTf2 (3.3(OTf)2). The reaction of 3.1 and (CuOTf)2·C7H8 afforded [LtBu(Cl)GeCu(μ-Cl)]2 (3.4) instead. The reaction of 3.1 and CuI or AuI in acetonitrile afforded a dimeric germylenecopper(I) [LtBu(Cl)GeCu(μ-I)]2 (3.5) and -gold(I) complex [LtBu(Cl)GeAuI] (3.7) respectively. Further reactivity of 3.5 and 3.7 with PPh3 afforded a copper(I) [LtBu(Cl)GeCuI(PPh3)] (3.6) and gold(I) complex [LtBu(Cl)GeAuI(PPh3)] (3.8), respectively. Chapter 4 describes the reaction of the N-heterocyclic carbene (NHC)-stabilized disilicon(0) complex [IPr→Si=Si←IPr] (4.1; IPr = :C{N(Ar)CH}2) with ArN3 in THF at room temperature to afford a mixture of the NHC-stabilized siladiimide [ArNSi(IPr)NAr] (4.2), triazene [{CHN(Ar)}2CN3Ar] (4.3) and the free carbene IPr.