The structure of the first tetrameric alpha-lithiated N-phenylphosphazene has been determined in the solid state and shown to persist in toluene solution, an observation that gives insight into the variation in stereoselectivity found for reactions of alpha-lithiated phosphazenes with aldehydes.
Gomez, G. R., Fernandez, I., Ortiz, F. L., Price, R. D., Davidson, M. G., Mahon, M. F., & Howard, J. A. K. (2007). A tetrameric lithiated phosphazene containing a lithium atom bound exclusively to four sp(3)-hybridized carbanionic centers: A key intermediate for understanding structure-reactivity relationships of phosphazenyllithium compounds. Organometallics, 26(3), 514-518. https://doi.org/10.1021/om0608354