OXIDATION OF FERROCENYL KETONES USING SELENIUM(IV) OXIDE - CRYSTAL AND MOLECULAR-STRUCTURES OF RACEMIC 2,3-DIFERROCENYL-1,4-DIPHENYLBUTANE-1,4-DIONE, RACEMIC AND MESO IFERROCENYL-1,4-BIS(4-BIPHYNYLYL)BUTANE-1,4-DIONE, AND FERROCENYLMETHYL(4-BIPHENYLYL)KETONE

Oxidation of the ferrocenyl ketones FcCH(2)COR 1 [Fc = (C5H5)Fe(C5H4); a R = Ph, b R = C6H4Ph-4] with selenium(IV) oxide provides only modes t yields of the corresponding 1,2-diketones FcCOCOR 2, but substantial yields of the 1,4-butanediones RCOCH(Fc)CH(Fc)COR 3 resulting from C- C coupling. Compounds 3 exist in two diastereoisomeric forms, racemic and meso, and crystal structures are reported for rac-3a, rac-3b and m eso-3b, as well as for 1b. (C) 1997 Elsevier Science S.A.