Photochemical route to unusual tri-tungsten ferrocenylacetylene cluster [W3{μ-η2,η2- (H)Ctriple bond; length of mdashCFc}2(CO)12] and a dimetallacyclodecatetraene [W2{μ-η2,η2,η2,η2- (Fc)Cdouble bond; length as m-dashC(H)C(H)double bond; length as m-dashC(

Low temperature photoreaction between tungsten hexacarbonyl and ferrocenylacetylene yielded two unusual metal containing stable compounds, the tritungsten cluster, [W3(μ-η2,η2- (H)Ctriple bond; length of mdashCFc)2(CO)12] (1), and ditungsten-1,4,5,8-ferrocenylcyclodecatetraene, [W2{μ-η2,η2,η2,η2-(Fc)Cdouble bond; length as m-dashC(H)C(H)double bond; length as m-dashC(Fc)C(Fc)double bond; length as m-dashC(H)C(H)double bond; length as m-dashC(Fc)}(CO)6] (2). Both compounds were characterised by IR and 1H and 13C NMR spectroscopy and their molecular structures established by single crystal X-ray diffraction methods.