Reduction of 1,4-dichlorobut-2-yne by titanocene to a 1,2,3-butatriene. Formation of a 1-titanacyclopent-3-yne and a 2,5-dititanabicyclo[2.2.0]hex-1(4)-ene

The 2,5-dititanabicyclo[2.2.0] hex-1(4)-ene (bis-titanocene-mu-(Z)1,2,3- butatriene complex) ( 3) is formed starting from [Cp2Ti(eta(2)-Me3SiC2SiMe3)] by in situ generated titanocene and 1,4-dichlorobut-2-yne via the 1-titanacyclobut-3-yne ( 2).