SYNTHESIS AND STRUCTURE OF A NEW-TYPE OF SANDWICH-LIKE YTTRIUM COMPLEX DERIVED FROM TETRAPHENYLETHYLENE - [NA(THF)(6)][Y(PH2CCPH2)(2)]

Yttrium trichloride reacts with both Na-2[Ph2CCPh2] and K-2[Ph2CCPh2], made from Ph2C=CPh2 and sodium and potassium mirrors, respectively, t o form complexes of general formula [M(THF)(x)][Y(Ph2CCPh2)(2)] (M = N a, 1; K, 2; x = 4-6). Complex 2 undergoes cation exchange with NaBPh4 in THF to form crystals of [Na(THF)(6)] [Y(Ph2CCPh2)(2)](THF)(2), 3, s uitable for X-ray diffraction. The anionic unit in 3, [Y(Ph2CCPh2)(2)] (-), has a sandwich-like structure in which each (Ph2CCPh2)(2-) dianio n has six carbon atoms oriented toward the metal center with Y-C dista nces ranging from 2.518(6) to 2.689(7) Angstrom.