The stoichiometric reaction between thiols and maleimide-functional poly(ester)s is demonstrated to be a quantitative, tolerant, mild and efficient method for polymer modification.

Thermolysis of Ru(PPh3)3(CO)H2 with the N-heterocyclic carbene bis(1,3-(2,4,6-trimethylphenyl)imidazol-2-ylidene) (IMes) results in C-C activation of an Ar-CH3 bond in one of the mesityl rings of the carbene ligand. Upon addition of IMes to Ru(PPh3)3(CO)H2 at room temperature in the presence of an alkene, C-H bond activation is observed instead. The thermodynamics of these C-C and C-H cleavage reactions have been probed using density functional theory.

Reaction of Al(OiPr)3 with the tris-phenol amine ligand L1H3 in toluene at ambient temperature results in the formation of the iso-propanol adduct [HOiPr.Al(L1)]. Single crystal X-ray diffraction analysis reveals the structure to be a hydrogen bonded dimer. Reaction of Al(OiPr)3 (or AlMe3) with L1H3 in THF affords the related, and structurally characterised THF adduct, [THF.Al(L1)]. Similar reaction of Al(OiPr)3 (or AlMe3) with the bis-phenol amine and tetra-phenol diamine ligands, L2H3 and L3H4, results in the formation and isolation of the complexes [Al(L2)]2 and [Al(L3)H] respectively, both of which have been structurally characterised via single crystal X-ray diffraction studies. Reaction of the alkoxide bridged dimer [Al(L2)]2 with the strong Lewis base HMPA results in the formation of the monomeric HMPA adduct [HMPA.Al(L2)] which was also structurally characterised. The adduct [HOiPr.Al(L1)] and the dimer [Al(L2)]2 were tested for their activity in the ring-opening polymerisation (ROP) of rac-lactide under solvent-free conditions (130 degrees C). Under the conditions employed [Al(L2)]2 failed to produce polymer after 48 h, in stark contrast to [HOiPr.Al(L1)] which after 24 h and 48 h produced narrow molecular weight polymer (24 h: yield=25%, Mn=14500 and PDI=1.05; 48 h: yield=65%, Mn=47700 and PDI=1.06).

Two unprecedented hydrogen bonds were observed in the adducts obtained by the reactions of an N‐heterocyclic carbene with a bulky phenol and with diphenylamine. In the former case, proton transfer yields an imidazolium aryloxide (1) containing the shortest C−H⋅⋅⋅O interaction seen to date and in the latter, the hydrogen atom remains bound to the organic acid but forms a unique N−H⋅⋅⋅C hydrogen bond (2).

A homologous and homoleptic series of stable Group 11 metal triazenide complexes with the general formula [M(L')](n) (M = Cu or Au, n = 2; M = Ag, n = 3) featuring the bulky triazenide ligand N,N'-bis(2,6-di-isopropylphenyl)triazene, L'H, have been prepared by the reaction of Li[L'] with the metal chlorides, CuCl, AgCl, and [(THT)AuCl], respectively, in a 1:1 stoichiometric ratio. The compounds [Cu(2)(L')(2)] and [Au(2)(L')(2)] crystallized as dimers with M...M separations of 2.4458(4) A and 2.6762(4) A, respectively. In comparison, the reaction of AgCl with Li[L'] results in the formation of the tri-silver complex [Ag(3)(L')(3)] with Ag...Ag separations of 3.01184(17) A, 2.95329(17) A, and 2.92745(16) A. Attempts to react the parent triazene system L'H with [Cu(Mes)] resulted in the formation of the novel tri-copper system [Cu(3)(L')(2)(Mes)]. In all cases the molecular structures of the resultant complexes have been unambiguously determined by single crystal X-ray diffraction experiments.

A series of multinuclear Copper(I) guanidinate complexes have been synthesized in a succession of reactions between CuCl and the lithium guanidinate systems Li{L} (L = Me(2)NC((i)PrN)(2) (1a), Me(2)NC(CyN)(2) (1b), Me(2)NC((t)BuN)(2)(1c), and Me(2)NC(DipN)(2) (2d) ((i)Pr = iso-propyl, Cy = cyclohexyl, (t)Bu = tert-butyl, and Dip = 2,6-disopropylphenyl) made in situ, and structurally characterized. The di-copper guanidinates systems with the general formula [Cu(2){L}(2)] (L = {Me(2)NC((i)PrN)(2)} (2a), {Me(2)NC(CyN)(2)} (2b), and {Me(2)NC(DipN)(2)} (2d) differed significantly from related amidinate complexes because of a large torsion of the dimer ring, which in turn is a result of transannular repulsion between adjacent guanidinate substituents. Attempts to synthesis the tert-butyl derivative [Cu(2){Me(2)NC((t)BuN)(2)}(2)] result in the separate formation and isolation of the tri-copper complexes [Cu(3){Me(2)NC((t)BuN)(2)}(2)(μ-NMe(2))] (3c) and [Cu(3){Me(2)NC((t)BuN)(2)}(2)(μ-Cl)] (4c), both of which have been unambiguously characterized by single crystal X-ray diffraction. Closer inspection of the solution state behavior of the lithium salt 1c reveals a previously unobserved equilibrium between 1c and its starting materials, LiNMe(2) and N,N'-di-tert-butyl-carbodiimide, for which activation enthalpy and entropy values of ΔH(‡) = 48.2 ± 18 kJ mol(-1) and ΔS(‡) = 70.6 ± 6 J/K mol have been calculated using 1D-EXSY NMR spectroscopy to establish temperature dependent rates of exchange between the species in solution. The molecular structures of the lithium complexes 1c and 1d have also been determined and shown to form tetrameric and dimeric complexes respectively held together by Li-N and agostic Li···H-C interactions. The thermal chemistry of the copper complexes have also been assessed by thermogravimetric analysis.

A series of unsymmetrical nickel -diketonate derivatives have been synthesised and structurally characterised for application as atmospheric-pressure metal-organic chemical vapour deposition (AP-MOCVD) precursors for nickel oxide.[a]

The inherently rapid ligand substitution kinetics associated with the novel and chemically compatible precursors, [MCl 3