The preparation and characterisation of bimetallic iridium(II) complexes containing derivatised bridging naphthalene-1,8-disulfur or 4,5-dithiolato acephenanthrylene ligands

Oxidative addition of the disulfide compounds naphtho[1,8-cd][1,2] dithiole, 2-tert-butylnaptho[1,8-cd][1,2] dithiole, 2,7-di-tert-butylnaphtho[1,8-cd][1,2] dithiole, 4,5-dithiaacephenanthrylene and the thio/sulfinyl and thio/sulfonyl compounds naphtho[1,8-cd][1,2] dithiole 1-oxide, and naphtho[1,8-cd][1,2] dithiole 1,1-dioxide respectively to [{Ir(mu-Cl)( cod)}(2)] give dinuclear Ir - Ir bonded Ir(II) compounds [{IrCl( cod)}(2)(mu(2)- 1,8- S-2- nap)] 1, [{IrCl(cod)}(2)(mu(2)- 1,8- S-2-2(t)Bu- nap)] 2, [{IrCl(cod)}(2)(mu(2)-1,8-S-2- 2,7-di-Bu-t-nap)}] 3, [{IrCl(cod)}(2)(mu(2)- 4,5- S-2-phenan)] 4, [{IrCl(cod)}(2)(mu(2)- 1- S, 8{ S(O)}- nap)] 5 and [{IrCl(cod)}(2)(mu(2)-1-S, 8-{S(O)(2)}- nap)] 6 where the di-sulfur ligands act as bridges between the two Ir( II) metal centres. The compounds were obtained in moderate to good yields as orange or deep red powders or crystalline solids. Five of the new complexes have been structurally characterised and were found to have Ir - Ir bond lengths in the range 2.7630(8) to 2.8113(11) Angstrom.