Metal salen complex

A metal salen complex is a coordination compound between a metal cation and a ligand derived from N,N′-bis(salicylidene)ethylenediamine, commonly called salen. The classical example is salcomine, the complex with divalent cobalt Co2+, usually denoted as Co(salen).[1] These complexes are widely investigated as catalysts and enzyme mimics.[2][3]

A square planar metal–salen complex. The M denotes the metal atom; R and R′ denote precursor ingredients.

The metal-free salen compound (H2salen or salenH2) has two phenolic hydroxyl groups. The salen ligand is usually its conjugate base (salen2−), resulting from the loss of protons from those hydroxyl groups. The metal atom usually makes four coordination bonds to the oxygen and nitrogen atoms.

  1. ^ Cite error: The named reference tsumaki was invoked but never defined (see the help page).
  2. ^ Baleizão, Carlos; Garcia, Hermenegildo (2006). "Chiral Salen Complexes: An Overview to Recoverable and Reusable Homogeneous and Heterogeneous Catalysts". Chemical Reviews. 106 (9): 3987–4043. doi:10.1021/cr050973n. PMID 16967927.
  3. ^ Decortes, Antonello; Castilla, Ana M.; Kleij, Arjan W. (2010). "Salen-Complex-Mediated Formation of Cyclic Carbonates by Cycloaddition of CO2 to Epoxides". Angewandte Chemie International Edition. 49 (51): 9822–9837. doi:10.1002/anie.201002087. PMID 20957709.