[Ph4P][(C5H6N3O3)M(CO)5] (M = Cr,Mo, W; C5H7N3O3 = 1,3‐Dimethyl‐cyanuric Acid). Organometallic Complexes of the 1,3‐Dimethylcyanurate Ligand

1,3‐Dimethylcyanuric acid (DMCH) forms on deprotonation and reaction with TlF its thallous salt Tl[DCM] ( 2 ) which is converted to the phosphonium salt [PPh₄][DCM] ( 3 ). On the reaction with M(CO)₆, the pentacarbonylmetalate salts [Ph₄P][(DMC)M(CO)₅], M = Cr ( 4a ), Mo ( 4b ) and W ( 4c ) are obtained. IR and NMR data of 4 reveal the DMC anion ( 1 ) to have coordination properties similar to those of pyridine. The crystal structures of 4a and 4c are reported.