115677-85-5Relevant academic research and scientific papers
Rates and mechanism of biphenyl synthesis catalyzed by electrogenerated coordinatively unsaturated nickel complexes
Amatore, Christian,Jutand, Anny
, p. 2203 - 2214 (1988)
When performed under a constant reductive driving force, the mechanism of coupling of aryl halides by nickel catalysts is found to proceed through a chain reaction involving Ni(O), Ni(I), Ni(II), and Ni(III) complexes. The propagation steps include the oxidative addition of PhBr to the electrogenerated unsaturated Ni0(dppe). The resulting PhNiIIBr(dppe) is reduced to PhNiI(dppe) via a single electron uptake. The latter undergoes an oxidative addition with PhBr to afford the trivalent nickel complex Ph2NiIIIBr(dppe) which reductively eliminates Ph-Ph to yield NiIBr(dppe). The cycle is closed by a further single electron transfer to the monovalent nickel which restores the starting zerovalent nickel. The different steps have been characterized independently from transient electrochemical data, and the rate constants of the three chemical steps have been determined. The cycle is initiated by the two-step reduction of NiIICl2(dppe) into Ni0(dppe), which readily reacts with bromobenzene. At low concentrations of bromobenzene, the oxidative addition of PhBr to the phenylnickel(I) complex is the rate-determining reaction, introducing then an apparent first-order dependence of the overall kinetics with PhBr. At larger concentrations the rate-determining step is the reductive elimination from Ph2NiIIIBr(dppe) to afford the biphenyl, and the chain tends to propagate with a rate independent of PhBr concentration. The implications of the above mechanism for nonelectrochemical situations involving a reducing metal and catalytic amounts of nickel salts as the coupling reagents are discussed.
Design and synthesis of monofunctionalized, water-soluble conjugated polymers for biosensing and imaging applications
Traina, Christopher A.,Bakus Ii, Ronald C.,Bazan, Guillermo C.
, p. 12600 - 12607 (2011/10/02)
Water-soluble conjugated polymers with controlled molecular weight characteristics, absence of ionic groups, high emission quantum yields, and end groups capable of selective reactions of wide scope are desirable for improving their performance in various
"Hairy" poly(3-hexylthiophene) particles prepared via surface-initiated Kumada catalyst-transfer polycondensation
Senkovskyy, Volodymyr,Tkachov, Roman,Beryozkina, Tetyana,Komber, Hartmut,Oertel, Ulrich,Horecha, Marta,Bocharova, Vera,Stamm, Manfred,Gevorgyan, Suren A.,Krebs, Frederik C.,Kiriy, Anton
, p. 16445 - 16453 (2010/02/16)
Herein, we present a new paradigm in the engineering of nanostructured hybrids between conjugated polymer and inorganic materials via a chain-growth surface-initiated Kumada catalyst-transfer polycondensation (SI-KCTP) from particles. Poly(3-hexylthiophen
