Synthetic and computational studies of group 3 and group 4 imido and hydrazido compounds

• Main Author: Mellino, Simona
• Other Authors: Mountford, Philip
• Published: University of Oxford 2017
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.736127

This Thesis describes the synthesis and reactivity of titanium-nitrogen multiply bonded compounds. Mechanistic and bonding studies on titanium imido, hydrazido and borylimido complexes as well as on a novel scandium borylimide recently reported in our research group were described. <b>Chapter 1</b> provides an introduction to Group 4 and Group 3 metal-nitrogen multiply bonded compounds including synthesis, bonding and reactivity of titanium imido, hydrazido, alkylidene hydrazido and borylimido complexes, (L)Ti=NR, (L)Ti=NNR₂, (L)Ti=NNCR₂ and (L)Ti=NBR₂. <b>Chapter 2</b> describes the reactions of the hydrazido compound Ti(N₂ ^iPrN^Me)(NNPh₂)(py) with the Si - H and B - H bonds of silanes and boranes and with H₂. The nature and mechanism of these reactions were investigated both computationally and experimentally. <b>Chapter 3</b> explores a series of new reactions and unprecedented transformations of organic boranes and silanes with titanium half-sandwich compounds. In addition, detailed mechanistic work, using DFT calculations, was performed to understand the chemistry behind these reactions. <b>Chapter 4</b> describes the bonding and reactivity of novel borylimido compounds. The systematic approach recently implemented in our research group to synthesise new titanium borylimido compounds, is described. A full computational study of the bonding of compounds with sandwich and half-sandwich structures is explained in detail. <b>Chapter 5</b> explores the experimental attempts to isolate the first scandium borylimido complex performed in our group. DFT and QTAIM and detailed mechanistic study are presented. <b>Chapter 6</b> contains experimental details, characterising data and DFT energies and coordinates of the optimized structures for the chemistry presented in Chapters Tw-Five.