β-Diketiminato Scandium Chemistry: Attempted Deprotonation of Cationic Amido Complexes
作者:Lisa K. Knight、Warren E. Piers、Robert McDonald
DOI:10.1021/om060197p
日期:2006.6.1
Treatment of the beta-diketiminato-supported scandium amido methyl derivatives [ArNC(Bu-t)CHC(Bu-t)NAr]Sc(Me)(NHR) (Ar=2,6-Pr-i(2)-C6H3; R=Bu-t, 2,6-Pr-i(2)-C6H3) with 1 equiv of tris(pentafluorophenyl) borane resulted in the formation of scandium amido ion pairs, 1a and 1b, respectively, in good yields. A single-crystal X-ray analysis of 1a was undertaken, and two crystallographically independent molecules were observed in which one contains an N-H center dot center dot center dot F-C hydrogen bond while the other does not. Several attempts to deprotonate the amido ligand to yield a neutral imido species resulted in either attack of the base at the metal center or deprotonation of the beta-diketiminato ligand. For example, treatment of 1a with tertbutyllithium gave [ArNC(Bu-t)CHC(Bu-t)NAr]Sc(CMe3)((NHBu)-Bu-t) (2), while treatment with the phosphazene base [(Me2N)(3)P=N](3)P=(NBu)-Bu-t gave the previously characterized metalated complex 3.