Description |
Propargylguanidines, accessible in three synthetic steps, when treated with metal catalysts undergo hydroaminations. Judicious choice of metal catalyst can lead to regioselective hydroaminations. Silver has been shown to catalyze a 5-exo-dig pathway, whereas rhodium catalyzes a 6-endo-dig pathway. Computational and kinetic data are used to identify potential reaction mechanisms and transition states of the Rh(II)- catalyzed hydroamination. The propargylguanidine hydroamination methodology has been expanded to include the cyclization of bis-propargylguanidines, to produce bicyclic guanidine structures. |