Synthesis, molecular structure and stability of fused bicyclic Δ4-1,2,4-oxadiazoline Pt(II) complexes

Abstract The reaction of trans -[PtCl 2 (NCR) 2 ] (R 1  = CH 2 CO 2 Me ( 1a ), R 2  = CH 2 Cl ( 1b )) with pyrroline N -oxide − O + N CHCH 2 CH 2 C Me 2 ( 4 ), at room temperature for 15 min, furnishes via [3+2] cycloaddition the fused bicyclic Δ 4 -1,2,4-oxadiazoline Pt(II) complexes trans- [PtCl 2 { N C(R)O N C(H)CH 2 CH 2 C Me 2 } 2 ] (R 1  = CH 2 CO 2 Me ( 5a ), R 2  = CH 2 Cl ( 5b )). Compounds 5a and 5b were refluxed in CH 2 Cl 2 for 1 week to afford the derived ketoimine Pt(II) complexes trans- [PtCl 2 {N(C( O)(R)) C CH 2 CH 2 C(Me 2 ) N H} 2 ] (R 1  = CH 2 CO 2 Me ( 6a ), R 2  = CH 2 Cl ( 6b )), respectively, as a result of the N–O bond cleavage of the oxadiazoline ring in 5 . The c…