SYNTHESIS AND X-RAY STRUCTURES OF THE 5-COORDINATE ZIRCONOCENE COMPLEXES PHP(CH2CH2-ETA(5)-C5H4)(2)ZRCL2, [PHP(CH2CH2-ETA(5)-C5H4)(2)ZRCL(H2O)]CL AND PHP(CH2CH2-ETA(5)-C5H4)(2)ZR(NCS)(2)

The five-coordinate zirconocene dichloride PhP(CH2CH2-eta(5)-C5H4)(2) ZrCl2 (3), containing a tethered bis(cyclopentadienyl)-phosphine ligan d, was prepared by treating a tetrahydrofuran solution of ZrCl4(thf)(2 ) with Li-2[PhP(CH2CH2C5H4)(2)]. An X-ray crystal structure analysis c onfirmed the phosphorus atom to be coordinated to the zirconium metal center. Dissolution of 3 in wet methanol followed by evaporation of th e solvent yielded the crystallographically characterized cationic chlo roaqua complex [PhP(CH2CH2-eta(5) C5H4)(2)ZrCl(H2O)](+) as the chlorid e salt (4). Treatment of an aqueous solution of 3 with excess thiocyan ate gave a good yield of the bis(isothiocyanato) complex PhP(CH2CH2-et a(5)-C5H4)(2)Zr(NCS)(2) (7), the structure of which was confirmed by X -ray crystallography. (C) 1997 Elsevier Science S.A.