Crystal structure of 1-ferrocenyl-4-phenyl-1,3-butadiyne, (C5H5)Fe(C15H9)

Abstract

C 20 H 14 Fe, monoclinic, P 12 1 / n 1(no. 14), a =6.297(2) Å, b =12.825(2) Å, c =18.487(4) Å, b =90.57(2)°, V =1492.9 Å 3 , Z =4, R gt (F) =0.077, wR ref (F 2 ) =0.216, T =293 K. -Ferrocenyl-4-phenyl-1,3-butadiyne (CARN 1272-90-8) represents an asymmetricmonomer precursor for conjugated electroactive array models. Amodern method for the directed synthesis of the title compound by Cadiot-Chodkiewicz coupling of phenylethynea nd 1-bromo-2-ferrocenylethyne mediated by CuCl/NH 2 OH in modest yield(38 %) has been reported [1], although astatistical approach from phenylethyneand ferrocenylethyne using Cu(OAc)2 /pyridine with better yield (50 %) has been long known [2]. Surprisingly, the use of CuCl/TMEDA [3] in anothers tatistical oxidative coupling reaction gave an even more satisfactoryyield (74 %) of 1-ferrocenyl-4-phenyl-1,3-butadiyne. Suitable crystals were obtained by slow evaporation of a diethylether/pentane solution. The structure of closely related 1,4-diferrocenyl-1,3-butadiyne, which can be conveniently prepared by strictly following the method described for 1,4-diphenylbutadiyne [4], has been published twice [5,6], and acrystal structure of anew dimorph has also recently been reported [7]. Source of material1 Discussion