Preferential Crystallization of (±)-pinenyllithium·TMEDA

Authors

Alexander N. Erickson, Marquette UniversityFollow
Curtis Haltiwanger, University of Colorado - Boulder
Masoumeh Rahim, University of Memphis
Charles M. Garner, University of Colorado - Boulder

Document Type

Article

Publication Date

7-2024

Publisher

Wiley

Source Publication

Acta Crystallographica Section C

Source ISSN

2053-2296

Original Item ID

DOI: 10.1107/S2053229624004662

Abstract

(±)-Pinenyllithium·TMEDA or (tetra­methyl­ethylenedi­amine-κ²N,N′)(η³-6,6-di­methyl-2-methylenebi­cyclo­[3.1.1]hept­yl)lithium, [Li(C₁₀H₁₅)(C₆H₁₆N₂)], is readily pre­pared from β-pinene, butyl­lithium and TMEDA, and the racemic material pre­fer­entially crystallizes even from 96:4 (92% ee) mixtures of (−)- and (+)-β-pinene, respectively. The structure is monomeric, with the geminal-dimethyl bridge of the bicyclic structure shielding one face of the allyl system, restricting the lithium to the opposite face and preventing the Li–all­yl–Li aggregation observed with some other allyl­lithium systems. The symmetry of the allyl system, bond lengths, bond angles and out-of-plane deviations are com­pared to existing structures. In addition, a much older structure of this com­plex is compared to this very recent one.

Comments

Acta Crystallographica Section C, Vol. 80, No. 7 (July 2024): 297-301. DOI.

Recommended Citation

Erickson, Alexander N.; Haltiwanger, Curtis; Rahim, Masoumeh; and Garner, Charles M., "Preferential Crystallization of (±)-pinenyllithium·TMEDA" (2024). Chemistry Faculty Research and Publications. 1096.
https://epublications.marquette.edu/chem_fac/1096