(3,3-DIPHENYLALLENYLIDENE)TRIMETHYLPHOSPHANE-TITANOCENE - THE 1ST TITANOCENE CARBENE COMPLEX WITH 3 CUMULATIVE DOUBLE-BONDS

1,2‐Dilithiocyclopropene → 1,1‐dilithioallene rearrangement results in the formation of compound 2 from 3,3‐diphenylcyclopropene (1) and two equivalents of n‐butyllithium. Compound 2 reacts further with titanocene dichloride and trimethylphosphane to give the allenylidenetitanocene complex 3. The yields of this one‐pot synthesis are 71 %. (Figure Presented.) Copyright © 1990 by VCH Verlagsgesellschaft mbH, Germany