The reactions of ethyl-(S)-(-)-lactate with R3Al in diethyl ether yield the pentacoordinated complexes [R2Al((S)-(-)-μ2-OC(H)(Me)C(O)OEt))]2 (1: R=Me; 2: R=Et; 3: R=Bui). These compounds have been characterized by spectroscopic studies as wells as crystallographic method. These structures show dimeric features containing unusual 5.4.5-fused rings with an Al2O2 core and the ester group bonded to Al through the CO. VT NMR studies of compound 3 suggest that the weak (CO)→M dative bond may undergo dissociation in solution, giving rise to the equilibrium with a four-coordinate species among two five-coordinate species at ambient temperature.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry