in not given

in dichloromethane; toluene ReO3(OSiMe3) and isocyanate in toluene refluxed for 24 h, removal of solvent in vac., redissolved in CH2Cl2, addn. of pyridine*HCl, 2 h; addn. of pentane, concn. in vac., filtered through Celite, reduced to dryness in vac., extn. (boiling benzene), filtered (ArNH3Cl and Py*HCl), concn. of filtrate, cooled, recrystn. (CH2Cl2/pentane); elem. anal.;