caa a22 4500 465775837 CHVBK 20180323111941.0 cr unu---uuuuu 170327e19900801xx s 000 0 eng 10.1007/BF01061941 doi (NATIONALLICENCE)springer-10.1007/BF01061941 Reductive versus coupling pathways in the reactions of nickel and copper vapours with the mono-halobenzenes [Elektronische Daten] [Scott Douglass, Scott Massey, Susan Woolard, Robert Zoellner] Summary: The reactions of nickel and copper vapours with mono-halobenzenes to form benzene and biphenyl are reported. Benzene formation apparently proceeds through the intermediacy of the phenyl radical, which is produced when metal clusters abstract halogen from the halobenzene. Biphenyl formation proceedsvia an oxidative insertion/disproportionation/reductive elimination sequence, and requires that metal atoms, rather than metal clusters, initiate the reaction sequence. The concentration of the metal in the matrix determines the pathway of the reaction. Cluster formation and benzene production are favouted by high metal concentrations, while low metal concentrations in the matrix favour biphenyl production. Copper vapours are anomalously less reactive than nickel vapours, even though copper reagents are used in the Ullmann reaction to produce biaryls through the coupling of haloarenes. This result appears to be due to the preferential formation of atoms or very small clusters over large clusters or crystallites under the conditions of the metal vapour synthesis technique. Chapman and Hall Ltd, 1990 Douglass Scott Department of Chemistry, Northern Arizona University, 86011-5698, Flagstaff, Arizona, USA aut Massey Scott Department of Chemistry, Northern Arizona University, 86011-5698, Flagstaff, Arizona, USA aut Woolard Susan Department of Chemistry, Northern Arizona University, 86011-5698, Flagstaff, Arizona, USA aut Zoellner Robert Department of Chemistry, Northern Arizona University, 86011-5698, Flagstaff, Arizona, USA aut Transition Metal Chemistry Kluwer Academic Publishers 15/4(1990-08-01), 317-324 0340-4285 15:4<317 1990 15 11243 https://doi.org/10.1007/BF01061941 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF01061941 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Douglass Scott Department of Chemistry, Northern Arizona University, 86011-5698, Flagstaff, Arizona, USA aut NATIONALLICENCE 700 1- Massey Scott Department of Chemistry, Northern Arizona University, 86011-5698, Flagstaff, Arizona, USA aut NATIONALLICENCE 700 1- Woolard Susan Department of Chemistry, Northern Arizona University, 86011-5698, Flagstaff, Arizona, USA aut NATIONALLICENCE 700 1- Zoellner Robert Department of Chemistry, Northern Arizona University, 86011-5698, Flagstaff, Arizona, USA aut NATIONALLICENCE 773 0- Transition Metal Chemistry Kluwer Academic Publishers 15/4(1990-08-01), 317-324 0340-4285 15:4<317 1990 15 11243 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer