Dibenzoazepine hydrazine is a building block for -alkene hybrid ligands: exploratory syntheses of complexes of Cu, Fe, and Li.

The new hydrazine 5-dibenzo[,]azepin-5-amine (2) reacts with P- and Si-electrophiles deprotonation to afford P(III)-, P(V)-, and TMS-hydrazides 3-8 and with carbonyl electrophiles acid-free condensation to the -substituted hydrazones 9-12 that are potential -alkene ligands. While β-ketohydrazone 9 and α-dihydrazone 10 react with [Mes(Cu)], [Cu(NCCCH)]PF, and FeCl(THF) to afford complexes devoid of alkene interaction, [Cu(OTf)]·CH reacts with the α-keto hydrazone 11 or with , dimethyl-hydrazone 12 to form the neutral dimeric Cu(I) complex 18 with bridging Cu(I)-alkene interactions or the tetrahedral cationic complex 19 in which 12 binds as a bidentate hydrazone-alkene ligand, respectively. The surprising stability of the alkene coordination in complexes 18 and 19 prevents substitutions with, , PPh.