Subphthalocyanines:: Singular nonplanar aromatic compounds-synthesis, reactivity, and physical properties

Subphthalocyanines are the lowest homologues of phthalocyanines, well-known two-dimensional 18 π-electron aromatic systems with unusual electrical and optical properties. A review is given on the synthesis and the chemical and physical properties of subphthalocyanines as well as their relatives subazarporphyrins2b,8p,18 and subnaphthalocyanines. 2b,e,4,8n,p,q,t,9d,18,19μ-Oxo dimeric subphthalocyanines,4a,8p,18 fused subphthalocyanines, 161,20 and subphthalocyanine-based electroactive dyads are also discussed.