Schiff base chemistry of the rhenium(V)-oxo core with ‘3+2’ ligand donor sets

Reactions of [ReOCl3(PPh3)2] with the bidentate ligands 2-(2-hydroxyphenyl) benzoxazole and (2′-hydroxyphenyl)-2-thiazoline resulted in the isolation of the complexes [ReOCl2(OC6H4-2-CNC6H4-2-O)(PPh3)] (1) and [ReOCl2(OC6H4-2-CNCH2CH2S)(PPh3)] (2). Reactions of 1 with the tridentate Schiff base ligands salicylaldehyde 2-hydroxyanil (H2L1b), salicylaldehyde 2-mercaptoanil (H2L2b) and S-benzyl-2-[(2-hydroxyphenyl)methylene] dithiocarbazate (H2L3b) yielded the ‘3+2’ rhenium(V) oxo species [ReO(OC6H4-2-CNC6H4O) (OC6H4CHNC6H4O)] (3), [ReO(OC6H4-2-CNC6H4O)(OC6H4CHNC6H4S)] (4) and [ReO(OC6H4-2-CNC6H4O){OC6H4CHN–NC(SCH2C6H5)S}] (5). Similarly, the reactions of [ReOCl2(OC6H4-2-CNC6H4S)(PPh3)] (2) with H2L2b, H2L3b and 2-[(2-hydroxyphenyl) methylene]-N-phenyl-hydrazinecarbothioamide (H2L4b) were exploited to prepare [ReO(OC6H4-2-CNC6H4S)(OC6H4CHNC6H4O)] (6), [ReO(OC6H4CNC6H4S){OC6H4CHN–NC (SCH2C6H5)S}] (7) and [ReO(OC6H4-2-CNC6H4S){OC6H4CHN–NC(NHC6H5)}] (8), respectively.