Phenanthrolines

1,10-Phenanthroline (phen) is a heterocyclic organic compound. It is a white solid that is soluble in organic solvents. The 1,10 refers to the location of the nitrogen atoms that replace CH's in the hydrocarbon called phenanthrene.

Ferroin, also known as tris(o-phenanthroline)iron(II), is the chemical compound with the formula [Fe(o-phen)3]SO4, where o-phen is the abbreviation of ortho-phenanthroline for 1,10-phenanthroline, a bidentate ligand. The term "ferroin" is used loosely and includes salts of other anions such as chloride. Ferroin is one of many transition metal complexes of 1,10-phenanthroline.

'Benzo[c]cinnoline' is a tricyclic organic compound with the formula C12H8N2. Formally this species is derived by oxidative dehydrogenation of 2,2'-diaminobiphenyl. This heterocycle reacts with iron carbonyls to form C12H8N2Fe2(CO)6.

Neocuproine is a heterocyclic organic compound and chelating agent. Phenanthroline ligands were first published in the late 19th century, and the derivatives substituted at the 2 and 9 positions are among the most studied of the modified phenanthrolines.

Phanquinone is an organic compound with the formula . It is derived by oxidation of 4,7-phenanthroline.