Ultrafast amidation of esters using lithium amides under aerobic ambient temperature conditions in sustainable solvents

• DOI: 10.1039/d0sc01349h
• Publication Date: 2020-04-30T10:46:26Z
• Authors: Michael Fairley; Leonie J. Bole; Florian F. Mulks; Laura Main; Alan R. Kennedy; Charles T. O'Hara; Joaquín García-Al...; Eva Hevia
• Keywords: Reactivity; Bond cleavage; Amide; Organic Synthesis

Lithium amides constitute one of the most commonly used classes reagents in synthetic chemistry. However, despite having many applications, their use is handicapped by requirement low temperatures, order to control reactivity, as well need for dry organic solvents and protective inert atmosphere protocols prevent fast decomposition. Advancing development air- moisture-compatible polar organometallic chemistry, chemoselective ultrafast amidation esters mediated lithium reported. Establishing a novel sustainable access carboxamides, this has been accomplished via direct C-O bond cleavage range using glycerol or 2-MeTHF solvent, air. High yields good selectivity are observed while operating at ambient temperature, without transition-metal mediation, protocol extends transamidation processes. Pre-coordination substrate reactive amide key step processes assessed, enabling structural elucidation coordination adduct [{Li(NPh2)(O[double bond, length m-dash]CPh(NMe2))}2] (8) when toluene employed solvent. No evidence formation complex type found donor THF Structural spectroscopic insights into constitution selected provided that support involvement small kinetically activated aggregates can react rapidly with substrates, favouring cleavage/C-N over competing hydrolysis/degradation moisture