Download or read book Low-Valent Cobalt Isocyanides written by Alex Edward Carpenter and published by . This book was released on 2015 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: A synthetic and structural investigation of cobalt complexes stabilized by m-terphenyl isocyanides was conducted. These species were studied as isolable mimics to unsaturated cobalt carbonyls and as platforms to access coordination complexes with unusual dn/valence combinations. Through these studies, a critical assessment of isocyanide for carbonyl substitution is presented. This assessment includes a comparative study on the electronic influence of isocyanides (C[equivalence]N--R), as a function of R-group identity, in Cr(CNR)(CO)5 complexes. Structural mimics to all three conformational isomers of Co2(CO)8 were prepared using the m-terphenyl isocyanides CNArMes2 (ArMes2 = 2,6-(2,4,6-Me3C6H2)C6H3) and CNArDipp2 (ArDipp2 = 2,6-(2,6-i-Pr2C6H3)C6H3). Solid-state X-ray diffraction data showed that 1,1-Co2(CO)6 (CNArMes2)2 adopts a "D2d-type" conformation, analogous to the elusive D2d isomer of Co2(CO)8. The cobalt hydride HCo(CNArMes2)4 was synthesized and structurally characterized. As a potential analogue to HCo(CO)4, a broad survey of its reactivity was undertaken. In the course of this study, HCo(CNArMes2)4 was found to mediate 1,1-hydrogenation and 1,1-hydrosilylation of CNArMes2. Complementing this work, a complete series of mixed carbonyl-isocyanide cobalt metallates, [Co(CO)4-n(CNArMes2)n]-, and hydrides, HCo(CO)4-n(CNArMes2)n, were prepared. The synthesis and solution-phase properties of a zwitterionic cobalt metallate is presented. 2D EXSY NMR studies and isotopic labeling experiments demonstrate that [Eta]2-PPNCo(CNArMes2)3, functions as a masked source of [Co(CNArMes2)3]1-, a 16 valence electron isocyano metallate. Electrophillic functionalization of [Eta]2-PPNCo(CNArMes2)3, with TMSCl, provided access to Co(SiMe3)(CNArMes2)3. This complex was structurally characterized by X-ray diffraction. The previously reported ability of Co(SiMe3)(CNArMes2)3 to form a [alpha]-complex with n-hexane at low-temperature in the solid state is contextualized with variable temperature IR and NMR studies. Reduction of Co(SiMe3)(CNArMes2)3 generated the highly reduced isocyano metallate K2[Co(SiMe3)(CNArMes2)3]. This dissertation concludes with the synthesis and characterization of the first examples of terminal transition metal antimony trifluoride (SbF3) and antimony difluoride (SbF2) complexes.