Lewis Acid Stabilized Methylidene and Oxoscandium Complexes

Abstract

The methylidene scandium complex (PNP)Sc(mu(3)-CH(2))(mu(2)-CH(3))(2)[Al(CH(3))(2)](2) (PNP=N[2-P(CHMe(2))2-4-methylpheyl](2)(-)) can be prepared from the reaction of (PNP)Sc(CH(3))(2) and 2 equiv of Al(CH(3))(3). The Lewis acid stabilized methylidenes candium complex has been crystallographically characterized, and its bonding scheme analyzed by DFT. In addition, we report preliminary reactivity studies of the Sc-CH(2) ligand with substrates such as H(2)NAr and OCPh(2). While the former results in an Bronsted acid-base reaction, the latter reagent produces the olefin H(2)C-CPh(2) along with the novel oxoscandium complex (PNP)Sc(mu(3)-O)(mu(2)-CH(3))(2)[Al(CH(3))(2)](2), quantitatively.