Metal Complexes of Functionalized Sulfur‐Containing Ligands. Part XIX

Abstract

Abstract The title compounds were prepared starting from the dihydropyrrolones 4 – 6 . Nucleophilic displacement and ring closure yielded the 1 H ‐pyrrolo[3,2‐ c ]isothiazol‐5(4 H )‐ones 8 and 10 . The fused systems formed salts with strong acids and electrophiles ( 15, 16 ), as well as with bases. Oxidation led either to S (2)‐oxides ( 18a, 20a ) or to the corresponding bicyclic sultams ( 18b, 20b ), depending on the reaction conditions. The sulfinamide 18a was also obtained from the known 1,2‐dithiolopyrrolone S ‐oxide 21 by a ring‐opening/ring‐closure reaction sequence. O ‐Methylation of 8 furnished the ‘azafulvene' 17 . The oxidative addition of [Pt( η 2 ‐C 2 H 4 )L 2 ] ( 24a : L=Ph 3 P, 24b : L=1/2 dppf, 24c : L=1/2 ( R , R )‐diop) to 18a and 20a led to the cis ‐amido‐sulfenato Pt complexes 25 and 26a – c , respectively.