The structure of the product of the Asinger reaction of acetophenone with n-butylamine and elemental sulfur is
still under debate. Two products have been proposed: a hexathiocanthione containing a C2S6 ring with an exocyclic thione
and a heptathiocane containing a CS7 ring. A single crystal X-ray study has shown that the heptathiocane structure is correct.
1H and 13C NMR investigations in solution confirm that the structure is maintained in solution and that there is no
evidence for the imine tautomer.