Cyclo-pentadienyl derivs. useful as ligands for olefin polymerisation catalysts - prepd. by Stobbe condensation of a cyclic ketone with a succinic acid ester, intramolecular condensation, hydrolysis, decarboxylation and then reduction

摘要

New cyclopentadienyl derivs. are of formula (I),where R, R1, R2 and R4 = H, 1-5 C alkyl, 5-8 C cycloalkyl, 6-8 C aryl and alkylaryl, 7-9 C aralkyl, provided the number of R different from H not > 2, excluding cpds. having n = 3; R = R1 = R2 = R4 = H; n = 2-18.