α-CC agostic structures and aggregation diversity in cyclopropyllithium derivatives.

In the presence of thf or tmeda and depending on experimental conditions, 1-phenylcyclopropyllithium may be crystallised as either dinuclear or tetranuclear species both exhibiting α-CC agostic distortions towards tricoordinate lithium cations. In thf solution, deaggregation of the dinuclear complex takes place to yield a well-defined mononuclear species [Li(thf)3(c-CPhC2H4)].