The new class of compounds arising from unconventinal additions of 1,4-disubstituted 1,3-butadiynes to activated permethylmetallocene species of Ti and Zr can be used in facile functionalizations. For example, the chiral product 5, obtained from the addition of tBuC=CC=CtBu to activated permethyltitanocene, has been derivatized by simple means, e.g., hydrogen chloride, bromine, or dihydrogen, affording practically useful functionalized titanocene compounds containing a chiral auxiliary ligand with an intramolecularly coordinated (compound 7) or a free double bond (compounds 8a,b).
The new complexes have been characterized spectroscopically. Additionally, X-ray crystal structure analyses were performed for 7 and 8a,b.