Dataset Information

Construction of heterometallic clusters with multiple uranium-metal bonds by using dianionic nitrogen-phosphorus ligands.

ABSTRACT: Compared with the prevalent metal-metal bond in transition metals, examples of the actinide-metal bond in heterometallic clusters are rare. Herein, a series of heterometallic clusters with multiple uranium-metal bonds has been prepared based on two newly synthesized nitrogen-phosphorus ligands L1 {O[(CH₂)₂NHP(ⁱPr)₂]₂} and L2 {[CH₂O(CH₂)₂NHP(ⁱPr)₂]₂}. Different P-P distances, 6.069 and 4.464 Å, are observed in the corresponding uranium complexes 1 {O[(CH₂)₂NP(ⁱPr)₂]₂UCl₂} and 2 {[CH₂O(CH₂)₂NP(ⁱPr)₂]₂UCl₂}, respectively, and lead to the different coordination modes with transition metals. The reactions of zero-valent group 10 metal compounds with complex 1 generate heterometallic clusters (3-U2Ni2 and 4-U2Pd2) featuring four uranium-metal bonds; whereas reactions with 2 afford one-dimensional metal-chain 5-(UNi)n, bimetallic species 6-UPd, and a tri-platinum bridged diuranium molecular cluster 7-U2Pt3. Complex 5-(UNi)n represents the first infinite chain containing the U-M bond and 7-U2Pt3 is the first species with multiple U-Pt bonds. This study further highlights the important role of ligands in the construction of multiple uranium-metal bonds and may allow the synthesis of novel d-f heterometallic clusters and the investigation of their applications in catalysis and small-molecule activation.

SUBMITTER: Feng G

PROVIDER: S-EPMC8152682 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Tertiary sulfonamide nitrogen-to-metal bonds of normal length are very rare. We recently discovered such a bond in one class of fac-[Re(CO)3(N(SO2R)(CH2Z)2)](n) complexes (Z = 2-pyridyl) with N(SO2R)dpa ligands derived from di-(2-picolyl)amine (N(H)dpa). fac-[M(CO)3(N(SO2R)(CH2Z)2)](n) agents (M = (186/188)Re, (99m)Tc) could find use as radiopharmaceutical bioconjugates when R is a targeting moiety. However, the planar, electron-withdrawing 2-pyridyl groups of N(SO2R)dpa destabilize the ligand to base and create relatively rigid chelate rings, raising the possibility that the rare M-N(sulfonamide) bond is an artifact of a restricted geometry. Also, the hydrophobic 2-pyridyl groups could cause undesirable accumulation in the liver, limiting future use in radiopharmaceuticals. Our goal is to identify a robust, hydrophilic, and flexible N(CH2Z)2 chelate framework. New C2-symmetric ligands, N(SO2R)(CH2Z)2 with (Z = CH2NH2; R = Me, dmb, or tol), were prepared by treating N(H)dien(Boc)2, a protected diethylenetriamine (N(H)dien) derivative, with methanesulfonyl chloride (MeSO2Cl), 3,5-dimethylbenzenesulfonyl chloride (dmbSO2Cl), and 4-methylbenzenesulfonyl chloride (tolSO2Cl). Treatment of fac-[Re(CO)3(H2O)3](+) with these ligands, designated as N(SO2R)dien, afforded new fac-[Re(CO)3(N(SO2R)dien)]PF6 complexes. Comparing the fac-[Re(CO)3(N(SO2Me)dien)]PF6 and fac-[Re(CO)3(N(SO2Me)dpa)]PF6 complexes, we find that the Re(I)-N(sulfonamide) bonds are normal in length and statistically identical and that the methyl (13)C NMR signal has an unusually upfield shift compared to that in the free ligand. We attribute this unusual upfield shift to the fact that the sulfonamide N undergoes an sp(2)-to-sp(3) rehybridization upon coordination to Re(I) in both complexes. Thus, the sulfonamide N of N(SO2R)dien ligands is a good donor, even though the chelate rings are conformationally flexible. Addition of the strongly basic and potentially monodentate ligand, 4-dimethylaminopyridine, did not affect the fac-[Re(CO)3(N(SO2tol)dien)]PF6 complex, even after several weeks. This complex is also stable to heat in aqueous solution. These results indicate that N(SO2R)dien ligands form fac-[Re(CO)3(N(SO2R)dien)]PF6 complexes sufficiently robust to be utilized for radiopharmaceutical development.

Dataset Information

Construction of heterometallic clusters with multiple uranium-metal bonds by using dianionic nitrogen-phosphorus ligands.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets