Heterodinuclear Cu(i)/Mo(vi) chemistry with bifunctional dibenzobarrelene ligands

Abstract

Bifunctional dibenzobarrelene ligands combining diphosphine with diol or other potentially bidentate functionalities are well-known mononucleating ligands for middle and late transition metals. These ligands generally exhibit tetradentate coordination, in which a metal is coordinated by [PC(sp3)P] 3-dimensional pincer and an additional alkoxide donor. These ligands can also be envisioned as heterodinucleating ligands, which coordinate a soft, late metal (via the diphospine) and a hard, early metal (via the diolate); the heterodinucleating reactivity of these ligands has not been studied. Herein we describe our initial studies on Cu(I)/Mo(VI) chemistry of the diphosphine/diol ligand L1H2; it is compared with the dibenzobarrelene ligand combining diphosphine with diester (L2). Both ligands led to stable Cu(I) complexes in which the ligand coordinates as a bidentate diphosphine. Spectroscopic characterization (carried out in CD2Cl2) revealed an AB system for the diastereotopic phosphine groups in 31P {1H} NMR spectrum. The phosphorus signals appear as an AB system due to the large values of 2JP–P, 120–150 Hz. 63Cu NMR spectroscopy (conducted in concentrated CD3CN solutions) revealed broad Cu signals at, or below, room temperature. The observation of a quadrupolar 63Cu (I = 3/2) signal was accompanied by the broadening of the 31P signals, which now appear as a single broad peak. The reaction of both ligands with (Et4N)2[MoO4] failed to form well-defined products. Treatment of [Cu(NCMe)2(L1H2)](PF6) with (Et4N)2[MoO4], followed by recrystallization from DMSO/ether, revealed the structure of a trinuclear complex [MoO22-O)2{Cu(DMSO)(L1H2)}2] in which one Mo(VI) center is linked with two Cu(I) centers via oxo bridging ligands. In DMSO solution, the trinuclear complex likely forms discrete ionic species [Cu(DMSO)2(L1H2)]2[MoO4] or [Cu(DMSO)2(L1H2)][Et4N][MoO4].

Graphical abstract: Heterodinuclear Cu(i)/Mo(vi) chemistry with bifunctional dibenzobarrelene ligands

Supplementary files

Article information

Article type
Paper
Submitted
06 Jun 2025
Accepted
09 Sep 2025
First published
10 Sep 2025
This article is Open Access
Creative Commons BY-NC license

Dalton Trans., 2025, Advance Article

Heterodinuclear Cu(I)/Mo(VI) chemistry with bifunctional dibenzobarrelene ligands

A. M. B. Chandima, G. Sgro, S. M. Hilditch, U. I. Kaluarachchige Don, C. L. Ward, D. P. Anderson, L. Herman, D. Gelman, R. L. Lord and S. Groysman, Dalton Trans., 2025, Advance Article , DOI: 10.1039/D5DT01337B

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements