A chiral Schiff's base/aluminium alkoxide initiator bearing a ligand derived from R-(+)-111'-binaphthyl-2,2'-diamine was synthesized and used for the stereoelective polymerization of rac-(o,L)-lactide. Rather high stereoelectivity is observed: a polymer with 88% enantiomeric enrichment in D units is obtained at 19% conversion. At high conversions a stereocomplex between D-and L-enriched stereocopolymers is formed. The polymerization --reaction shows living type features, and narrow molecular weight distributions (MJM" = 1,05-1,30) are obtained up to very high conversions. This indicates that transesterification reactions do not occur significantly with this sterically hindered initiator.

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Not a reductive rupture, but a strengthening of the AlAl bond is the result of the reduction of the dialane 1 with lithium. The salt isolated after addition of TMEDA contains the radical anion of 1, in which, as results of an X‐ray structural analysis show, the AlC bonds are distinctly longer (+0.06 Å) and the AlAl bond considerably shorter (−0.13 Å) than in 1 itself. These findings are in accord with results of MO calculations, which indicate a stabilization of the AlAl bond by the additional electron.

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