Syntheses and molecular structures of some compounds containing many-atom chains end-capped by tricobalt carbonyl clusters

Several complexes containing Co3 carbonyl clusters end- capping carbon chains of various lengths are described. Pd( 0)/ Cu( I)- catalysed reactions between {Co3{l3- C( C, C) 2Au( PPh3)}( l- dppm)( CO) 7 and I( C, C) 2SiMe3 or FcC, CI gave {Co3{l3- C( C, C) xR}( l- dppm)( CO) 7 [ x = 4, R = SiMe3 3; x = 3, R = Fc 8]; treatment of 3 with NaOMe and AuCl( PPh3) gave 4 [ x = 4, R = Au( PPh3)]. Related preparations of Co3{l3C( C, C) 2[ Ru( PP) Cp0]}( l- dppm) n( CO) 9 2n [ PP = ( PPh3) 2, Cp' = Cp, n = 1, 5; PP = dppe, Cp0 = Cp*, n = 1, 6; 0, 7] are also described. Syntheses of bis- cluster complexes {Co3( l- dppm)( CO) 7} 2( l- Cx) ( x = 14, 12; 16, 9; 18, 11; 26, 10) - the latter being the longest cluster- capped Cx chains so far described - and the mercurybridged compounds Hg{( C, C) xC[ Co3( l- dppm)( CO) 7]} 2 ( x = 1, 13; 2, 14) are reported. The molecular structures of 7, 12, 13 and 14, as well as of Co3( l3- CC, CSiMe3)( l- dppm)( CO) 6( PPh3) ( 15) and Co3{l3CC( O) OEt}( l- dppm)( CO) 7 ( 16), are reported. (c) 2008 Elsevier B. V. All rights reserved.