ADDUCTS OF CYCLOPENTADIENYL SODIUM AND METHYLCYCLOPENTADIENYL SODIUM WITH OXYGEN BASES AND NITROGEN BASES - STRUCTURE OF CYCLOPENTADIENYLSODIUMTETRAMETHYLETHYLENEDIAMINE, NA(C5H5)(ME2NCH2CH2NME2)

The capacity of cyclopentadienylsodium to form adducts with the following bases has been studied: diethyl ether, tetrahydrofuran, 1,2-dimethoxyethane, 1,4-dioxane, 1,3,5-trioxane, benzo-15-crown-5, triethylamine, tetramehtylethylenediamine, pyridine, 4-dimethylaminopyridine, and 2,2′ bipyridryl. Most form extremely air- and moisture-sensitive 1 : 1 adducts Na(C5H5)L, where L = Lewis base. Similar adducts, Na(C5H4Me)L, of methylcyclopentadienylsodium have been prepared. Their infrared and 1H NMR spectra are consistent with η5-coordination of the cyclopentadienyl groups. In the crystal, the tetramehtylehtylenediamine adduct, Na(C5H5)TMEDA, adopts a puckered chain structure, with η5-C5H5 rings bridging Na(TMEDA) units. © 1979.