Carbonylative formation of N-acetyl-2,6-difluorobenzamide through N–H bond activation of 2,6-difluorobenzamide with Ni(II) complex supported with phosphine ligands

Fluorinated imide, N-acetyl-2,6-difluorobenzamide (C6H3F2-2,6)C(O)NHC(O)Me 2, could be obtained through one-pot reaction of NiMe2(PMe3)3 with 2,6-difluorobenzamide (C6H3F2-2,6)C(O)NH21 in CO atmosphere. A postulated reaction mechanism via N–H bond cleavage and carbonylative reductive elimination on nickel center was partly experimentally confirmed. An important intermediate (C6H3F2-2,6)C(O)HNNiMe(PMe3)23 was isolated and structurally characterized.

Graphical abstractFluorinated imide, N-acetyl-2,6-difluorobenzamide (C6H3F2-2,6)C(O)NHC(O)Me 2, could be obtained through one-pot reaction of NiMe2(PMe3)3 with 2,6-difluorobenzamide (C6H3F2-2,6)C(O)NH21 in CO atmosphere. A postulated reaction mechanism via N–H bond cleavage and carbonylative reductive elimination on nickel center was partly experimentally confirmed. An important intermediate (C6H3F2-2,6)C(O)HNNiMe(PMe3)23 was isolated and structurally characterized.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Carbonylation of benzamide. ► N–H bond activation by nickel complex. ► Insertion of carbonyl ligand. ► methyl nickel complex supported by trimethylphosphine.