The first synthesis of pyridinium N-benzoylguanidines by bismuth- and mercury-promoted guanylation of N-iminopyridinium ylide with thioureas

This work describes the first successful synthesis of five pyridinium N-benzoylguanidines. These new pyridinium ylides were prepared in moderate to good yields through the guanylation reaction of N-iminopyridinium ylide with N-benzoylthioureas, using both bismuth nitrate and mercury chloride as inorganic thiophiles. X-ray analysis of one pyridinium N-benzoylguanidine was investigated and the E configuration assigned. Intermolecular interactions of the type C–H⋯O and C–H⋯π were observed in the solid state. The results related in this study represent the first description of a ylide as the nucleophilic partner in the guanylation reaction.