Crystal structure of trimeric (2,6-di-tert-butoxyphenyl)lithium.
In: Organometallics, Jg. 10 (1991) ; Nr. 5, S. 1623-1627
Zeitschriftenaufsatz / Fach: Chemie
The structure of the title compd. has been detd. by single-crystal x-ray diffraction. The structure reveals a trimeric aggregate, which is rather unique in organolithium chem. The trimer is stabilized by intramol. coordination bonds between lithium and the ortho-positioned tert-BuO-substituents. Because of the bulky tert-BuO-substituents, the favored trigonal bonding geometry around the ether oxygen has been distorted to pyramidal for some of the oxygen atoms. The small but significant difference in Li-O(trigonal) and Li-O(pyramidal) bond distances has been evaluated by ab initio calcns. and can be explained by using electrostatic arguments.