Simultaneous cyclisation and coordination of dithizone to the fac-[Re(CO)3]+ core

The reaction of dithizone (H2dtz) with [Re(CO)5Cl] led to the complex fac-[Re(CO)3(Hdtz)(dttz)] (1). The ligand 1,2-diphenyltetrazolethione-5 zwitterion (dttz) was formed from the cyclisation of dithizone ligand, and both N,S-donor Hdtz− anion and S-donor dttz zwitterion coordinate to the fac-[Re(CO)3]+ giving fac-[Re(CO)3(Hdtz)(dttz)] (1). [Display omitted] •Cyclisation of dithizone in 2,3-diphenyl-5-thione-tetrazolium zwitterion.•Coordination of dithizone to the fac-[Re(CO)3]+ core as a bidentate N,S-donor ligand.•Coordination of 2,3-diphenyl-5-thione-tetrazolium zwitterion to the fac-[Re(CO)3]+ core as a monodentate S-donor ligand.•The conversion a bidentate N,S-donor ligand to monodentate S-donor ligand. The reaction of dithizone (H2dtz) with an organometallic rhenium(I) precursor; [Re(CO)5Cl] in ethanol led to the isolation of the octahedral organometallic fac-[Re(CO)3]+ core complex fac-[Re(CO)3(Hdtz)(dttz)] (1). The chelating ligand 1,2-diphenyltetrazolethione-5 zwitterion (dttz) in 1 was formed from the double deprotonation and cyclisation of dithizone in ethanol. The cyclisation of H2dtz to dttz zwitterion is a good example of the conversion of N,S-donor dithizone to S-donor ligand. Both dithizone anion Hdtz− and neutral zwitterion dttz coordinated to the fac-[Re(CO)3]+ core in which Hdtz− is coordinated as bidentate chelate via thiolate sulfur and azoic nitrogen atoms while dttz coordinated as monodentate ligand via thione sulfur atom. In addition to the synthesis, infra-red, 1H NMR, electronic properties and X-ray crystal structure of the complex 1 are reported.