Model for a superbase: synthesis and crystal structure of the mixed-metal/mixed-anion aggregate[NaLi_2{N(H)R}_2(OR′)]_2

摘要

The first structurally characterised example of a hetero-bis-s-block-metal amide-alkoxide complex, [NaLi_2{N(H)R}_2-(OR′)]_2 (1, R=2-methoxyphenyl, R′=tert-butyl), has been shown to be constructed from fusing four LiNNaO heterobimetallic rings with two Li_2N_2 rings through shared edges to form a cyclic ladder; the complex may serve as a model for “superbases” that are widely employed in organic synthesis.