2-[ethyl-(2-methallyl)amino]indenyllithium: Structural characterization ofa base-free oligomeric supersandwich indenyllithium compound

Treatment of the enamine 2, formed by condensation of 2-indanone and ethyl( 2-methallyl) amine, with n-butyllithium yields 2-[ethyl(2-methallyl)amino]i ndenyllithium (3), whose structure was determined by X-ray single crystal d iffraction, Complex 3 exhibits an oligomeric supersandwich structure in the solid state, characterized by a linear string of alternating mu-eta (5):et a (5)-indenyl anion and lithium cation moieties along which the substituent s are found attached in a helical-conformational arrangement.