ETHYNYLFERROCENE COMPOUNDS OF 1,3,5-TRIBROMOBENZENE

The new compounds 1,3-dibromo-5-(ferrocenylethynyl)benzene (1), 1-brom o-3,5-bis(ferrocenylethynyl)benzene (2), and 1,3,5-tris(ferrocenylethy nyl)benzene (3) have been synthesized by palladium-catalyzed cross-cou pling reactions and characterized, and the crystal structures of 1 and 3 have been determined; electrochemical studies show chemically rever sible oxidations with single-step one-electron, two-electron, and thre e-electron processes per molecule, respectively, indicating that in 2 and 3 the iron(II) centers do not electronically communicate with each other.