Indigo diimines (“Nindigo”): a new bridging ligand architecture with redox and near‐IR absorbing properties Robin G. Hicks, Department of Chemistry, University of Victoria Victoria, B.C. Canada Reactions of indigo with a variety of substituted anilines produce the corresponding indigo diimines (′Nindigos′) in good yields. The Nindigo ligand consists of two fused b‐diketiminate‐type binding sites for metals. Accordingly, binuclear Pd complexes have been obtained in which the deprotonated Nindigo bridges two Pd(hfac) moieties in the expected bis‐ bidentate binding mode. The complexes possess intense electronic absorption bands in the near‐infrared (near 920 nm, extinction coefficients ~ 104 M‐1∙cm‐1) which are ligand‐centered (π−π*) transitions. Cyclic voltammetry investigations reveal multiple redox events which are also ligand‐centered in origin. F3C
CF3
O O
N H
R H N
R-NH2 TiCl4, DABCO PhBr
O
N
N H
R H N
N Pd(hfac)2
N N
N R
indigo
O
Pd
Nindigo
O F3C
Pd
N
O CF3
R
