PEPPSI-IPr catalyst; lithium bromide in tetrahydrofuran; 1,3-dimethyl-imidazolidin-2-one Negishi coupling reaction; 0.5 h; Inert atmosphere;

[1,3-bis(diphenylphosphino) propane] dichloronickel(II) in tetrahydrofuran T=20°C; Negishi coupling reaction; 12 h; Inert atmosphere;

cobalt(II) 2,4-pentanedionate; lithium bromide in tetrahydrofuran; 1-methyl-pyrrolidin-2-one T=-30 - 0°C; 0.5 h;

in further solvent(s) 8.76 g CuI and 50 g Zn powder vacuum-treated for 10 min; dry oxygen-freeAr passed; butyl bromide and ethylzinc bromide soln. in butyl bromide; mixed; stirred at 50°C; stirred at 50°C; solid residue vac uum distd.;;

dichloro bis(acetonitrile) palladium(II) in N,N-dimethyl-formamide T=50°C; 12 h;

cobalt(II) 2,4-pentanedionate; lithium bromide in tetrahydrofuran; 1-methyl-pyrrolidin-2-one T=-30 - 0°C; 0.5 h;

in further solvent(s) 8.76 g CuI and 50 g Zn powder vacuum-treated for 10 min; dry oxygen-freeAr passed; propyl bromide and ethylzinc bromide in propyl bromide sol. added; stirred at 50.degree C; cooled to room temp.; solid residue remov ed;; vac. distn.; GLC;