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Scientific Publications of Jos Aerts

Weak S-O and S-N Bonds in Heterocyclic Systems: Crystal Structures of Three Thiapentalenes

J.Aerts and G.S.D.King

Bull.Soc.Chim.Belg., 106, 573-576 (1997)


The structures of two symmetrical thiapentalenes, one with an O-S-O and the other with an N-S-N group have been determined by single crystal X-ray diffraction methods in order to find the S-O and S-N bond lengths corresponding to a bond order of 0.5. The structure of a third, asymmetrical thiapentalene with an N-S-N group, together with a study of similar molecules in the Cambridge Structural Database suggest a sharp distinction between true thiapentalenes with an aromatic ring system and the pseudo-thiapentalenes which have no symmetry in the bonding system.