Structure and properties of metal complexes of a pyridine based oxazolidinone synthesized by atmospheric CO2 fixation

Abstract

We present here the synthesis of a pyridine containing oxazolidinone, 3-(pyridin-2-ylmethyl)oxazolidin-2-one (L) through the fixation of atmospheric CO₂ and without any added base. L has been used to generate three metal complexes [Cu(L)₂(ClO₄)₂] (1), trans-[Pt(L)(DMSO)Cl₂] (2), and trans-[Pd(L)₂Cl₂] (3). Complexes 1–3 have been structurally characterized using single crystal X-ray diffraction and other analytical techniques. The activity studies of the three metal complexes show that the Cu^II complex, 1, is more cytotoxic against the MCF-7 cancer cell line (IC₅₀ = 114 ± 2 μM) as compared to a non-carcinogenic mouse fibroblast (NIH 3T3) (IC₅₀ = 198 ± 1 μM). The Pt^II complex, 2, is the most toxic among the three complexes against both human breast adenocarcinoma (MCF-7) (IC₅₀ = 102 ± 2 μM) and the human lung adenocarcinoma epithelial cell line (A549) (IC₅₀ = 198 ± 2 μM), whereas the Pd^II complex, 3, is found to be an effective first generation oxazolidinone based Pd^II catalyst, for the Suzuki–Miyaura cross coupling of aryl halides and phenylboronic acids in aerobic conditions, both in a conventional heating method, as well as a microwave method. The results show that although Pt^II and Cu^II were also complexed with oxazolidinone, Pd^II seems to be the most likely choice of metal when it comes to C–C bond coupling via C–X bond activation.