Tracking the dissolution–recrystallization structural transformation (DRST) of copper(II) complexes: a combined crystallographic, mass spectrometric and DFT study

• Published in: Acta crystallographica. Section C, Crystal structure communications Crystal structure communications, 2020-07, Vol.76 (7), p.655-662
• Main Authors: Deng, Qian-Jun, Chen, Min, Chen, Dong-Chu, Long, Hang-Yu, Chen, Chang-Ai
• Format: Article
• Language: English
• Subjects: Anticancer properties; antiproliferative effect; Coordination compounds; Copper; Copper compounds; Copper converters; copper(II); crystal structure; Crystallography; Density functional theory; DFT; Dissolution; dissolution‐recrystallization structural transformation; DRDT; Ions; Mass spectrometry; Methanol; Recrystallization; Scientific imaging; Spectroscopy; Time dependence
• ISSN: 2053-2296; 0108-2701; 2053-2296; 1600-5759
• DOI: 10.1107/S2053229620006701

Methanol‐ and temperature‐induced dissolution–recrystallization structural transformation (DRST) was observed among two novel CuII complexes. This is first time that the combination of X‐ray crystallography, mass spectrometry and density functional theory (DFT) theoretical calculations has been used to describe the fragmentation and recombination of a mononuclear CuII complex at 60 °C in methanol to obtain a binuclear copper(II) complex. Combining time‐dependent high‐resolution electrospray mass spectrometry, we propose a possible mechanism for the conversion of bis(8‐methoxyquinoline‐κ2N,O)bis(thiocyanato‐κN)copper(II), [Cu(NCS)2(C10H9NO)2], Cu1, to di‐μ‐methanolato‐κ4O:O‐bis[(8‐methoxyquinoline‐κ2N,O)(thiocyanato‐κN)copper(II)], [Cu2(CH3O)2(NCS)2(C10H9NO)2], Cu2, viz. [Cu(SCN)2(L)2] (Cu1) → [Cu(L)2] → [Cu(L)]/L → [Cu2(CH3O)2(NCS)2(L)2] (Cu2). We screened the antitumour activities of L (8‐methoxyquinoline), Cu1 and Cu2 and found that the antiproliferative effect of Cu2 on some tumour cells was much greater than that of L and Cu1. Methanol‐ and temperature‐induced dissolution–recrystallization structural transformation (DRST) was observed among two novel CuII complexes. This is first time that the combination of X‐ray crystallography, mass spectrometry and density functional theory (DFT) theoretical calculations has been used to describe the fragmentation and recombination of a mononuclear CuII complex at 60 °C in methanol to obtain a binuclear copper(II) complex.