| abstract |
The invention relates to a process for the preparation of a compound of the formula IV or IVa (see formula IV and IVa) in which R1-R5 are preferably hydrogen or alkyl, which comprises reacting a compound I (see formula I) with a compound II (see formula II) in which X1 and X2 are preferably halogen, to give the corresponding indanones, which are converted into the compounds IV and IVa by reduction and dehydra-tion. The compounds IV and IVa are important intermediate products for the preparation of chiral metallocene complexes which are suitable catalyst components for olefin polymerization. |