Bruce, Michael IanCole, MarcusSumby, Christopher JamesParker, Christian Richard2011-08-052011-08-052010http://hdl.handle.net/2440/65307Chapter 1 outlines the potential application of metal alkynyl complexes and then describes the different methods in the literature for the synthesis of alkynyl, poly-ynyl and homo- and hetero-metal complexes. Their chemistry will then be discussed. This Chapter concludes with an outline of the work to be described in the remainder of the thesis. Chapter 2 describes a series of complexes containing a new tricyanovinylethynyl (3,4,4-tricyanobut-3-en-1-ynyl) ligand obtained by direct substitution of a CN group in tetracyanoethene by ethynyl complexes M(C=CH)(PP)Cp' [M = Ru, Os, (PP)Cp' = (PPh₃)₂Cp; M = Ru, PP = dppe, Cp' = Cp, Cp*]. The reactions proceed in higher yield as the metal environment becomes sterically larger and more donating; the normal [2 + 2]-cycloaddition / ring-opened product M{C[=C(CN)₂]CH=C(CN)₂}(PP)Cp' is also formed in some cases. The diynyl Ru(C=CC=CH)(dppe)Cp* reacts with tcne to give only the ring-opened adduct Ru{C=CC[=C(CN)₂]CH=C(CN)₂}(dppe)Cp*. Protonation of Ru{C=CC(CN)=C(CN)₂}(dppe)Cp* (10) afforded the vinylidene. A second transition metal fragment {MLn} [{MLn} = Ru(PPh₃)₂Cp, M'(dppe)Cp* (M' = Ru, Os), RuCl(dppe)₂] can be added to the CN group trans to the first. Compound 10 ready undergoes substitution of the 3-cyano group by nucleophiles. Some unexpected rearrangements and formation of O- and N-heterocyclic compounds were also found. Chapter 3 describes reactions between 1,2 dichlorohexafluorocyclopentene and Ru(C=CH)(dppe)Cp* (1) or Ru(C=CC=CLi)(dppe)Cp* which give Ru(C=C-c-C₅F₆Cl-2)(dppe)Cp* (36) and Ru(C=CC=C-c-C₅F₆Cl-2)(dppe)Cp*, respectively. Ready hydrolysis of 36 to Ru{C=C[c-C₅F₄Cl(O)]}(dppe)Cp* occurs, which can be converted to Ru{C=C(c-C₅F₄Cl[=C(CN)₂])}(dppe)Cp* by treatment with CH₂(CN)₂ / basic alumina. The cyano-fluorocarbon ligand in the latter is one of the most powerfully electron-withdrawing groups known. Chapter 4 describes the three methods of synthesising heterometallic carbon-chain complex {Cp*(dppe)Ru}C=CC=CC=CC{Co₃(μ-dppm)(CO)₇} (40), in two examples showing the first examples of Ru{(C=C)xI}(dppe)Cp* (x = 1, 2) being used in a cross coupling reaction with Ph₃ PAu(C=C)(₃-x)C{Co₃(μ-dppm)(CO)₇}. The reactivity of 40 with PPh₃, MeOTf, tcne, tcnq, Fe₂(CO)₉, NiCp₂ and Co₂(CO)₈ took place on either the C₈ bridge or on either metal centre. Chapter 5 discusses the reaction of 1 with oxalyl chloride which gave {Cp*(dppe)RuC=C}₂CO (52). This complex can be methylated to give [{Cp*(dppe)RuC=C}₂C(OMe)]OTf, which in turn can be protonated to the dication. Knövenagel condensation of 52 with CH₂(CN)₂ gave {Cp*(dppe)RuC=C}₂C{=C(CN)₂}. The reaction of 1 and bis(2,4-dinitrophenyl) oxalate afforded {Cp*(dppe)Ru}{c- C=C[C₆H₃(NO₂)₂]C(O)C(O)O}. The transmetallation reaction of {(Ph₃P)AuC=C}₂CO and RuCl(dppe)Cp unexpectedly gave the cyclic complex [1,4-{Cp(dppe)Ru}₂{c- COC(OMe)=CHCCH}]PF₆. Chapter 6 gives an account of the electrochemistry of many of these redox-active compounds and examines the UV-Vis absorption of the more polarised compounds. Some discussion of the various observed trends is presented. There is also a future direction of this chemistry given at the end of this work.ruthenium; alkynyl; cyanocarbons; fluorocarbons; odd-numbered carbon chains; ethynyl ketoneThesis20110622144447