Li vs Na: Divergent Reaction Patterns between Organolithium and Organosodium Complexes and Ligand-Catalyzed Ketone/Aldehyde Methylenation.

Organosodium chemistry is underdeveloped compared with organolithium chemistry, and all the reported organosodium complexes exhibit similar, if not identical, reactivity patterns to their lithium counterparts. Herein, we report a rare organosodium monomeric complex, namely, [Na(CHSiMe)(MeTren)] (-Na) (MeTren: tris[2-(dimethylamino)ethyl]amine) stabilized by a -dentate neutral amine ligand MeTren. Employing organo-carbonyl substrates (ketones, aldehydes, amides, ester), we demonstrated that -Na features distinct reactivity patterns compared with its lithium counterpart, [Li(CHSiMe)(MeTren)] (-Li). Based on this knowledge, we further developed a ligand-catalysis strategy to conduct ketone/aldehyde methylenations, using [NaCHSiMe] as the CH feedstock, replacing the widely used but hazardous/expensive C═O methylenation methods, such as Wittig, Tebbe, Julia/Julia-Kocieński, Peterson, and so on.