Isolation and crystal structure of a presumed intermediate in the reaction of an organolithium compound with an epoxide

Abstract

Geometries. Table VI compares the calculated (AM1) geometries with experiment. The mean unsigned error in bond lengths is 0.12 A, and the signed error 4 .10 A. The calculated aluminum bond lengths are thus systematically too short, a tendency already noted in AML4 AM1, like MND0,7 predicts the linear (Al-O-A1-0) forms of both A1202 and A1202+ to be more stable than the previously assumed square-planar st ructura, while NOH is predicted to be linear rather than bent. Further studies of these molecules would be of interest. Conclusions. We have produced a useful set of AM1 parameters for aluminum. The results from calculations using our values are generally closer to experimental than either MNDO or Stewart’s newly introduced PM3.