A novel rhenium(III) complex with bis(pyrazol-1-yl)methane: X-ray structure and DFT calculations for [ReCl3(bpzm)(PPh3)]

The [ReCl3(MeCN)(PPh3)2] complex reacts with bis(pyrazol-1-yl)methane (bpzm) to give [ReCl3(bpzm)(PPh3)]. This compound has been studied by IR, UV–Vis spectroscopy, magnetic measurement and X-ray crystallography. The molecular orbital diagram of [ReCl3(bpzm)(PPh3)] has been calculated with the density functional theory (DFT) method. The spin-allowed triplet–triplet electronic transitions of [ReCl3(bpzm)(PPh3)] have been calculated with the time-dependent DFT method, and the UV–Vis spectrum of the title compound has been discussed on this basis. The magnetic behavior is characteristic of a mononuclear d4 low-spin octahedral Re(III) complex (3T1g ground state) and arises because of the large spin–orbit coupling (ζ = 2500 cm−1), which gives a diamagnetic ground state.

Graphical abstractThe [ReCl3(MeCN)(PPh3)2] complex reacts with bis(pyrazol-1-yl)methane (bpzm) to give [ReCl3(bpzm)(PPh3)]. The compound has been studied by IR, UV-Vis spectroscopy and X-ray crystallography. The molecular orbital diagram of [ReCl3(bpzm)(PPh3)] has been calculated with the density functional theory (DFT) method. The spin-allowed triplet–triplet electronic transitions of [ReCl3(bpzm)(PPh3)] have been calculated with the time-dependent DFT method, and the UV–Vis spectrum of the title compound has been discussed on this basis. The magnetic behavior is characteristic of mononuclear complexes with d4 low-spin octahedral Re(III) complexes (3T1g ground state) and arise because of the large spin–orbit coupling (ζ = 2500 cm−1), which gives diamagnetic ground state.Figure optionsDownload full-size imageDownload as PowerPoint slide