Advances in heavy alkaline earth chemistry provide insight into complexation of weakly polarizing Ra2+, Ba2+, and Sr2+ cations

被引：5

作者：

Gilhula, J. Connor ^{[1
]}

Xu, Lei ^{[1
]}

White, Frankie D. ^{[1
]}

Adelman, Sara L. ^{[1
]}

Aldrich, Kelly E. ^{[1
]}

Batista, Enrique R. ^{[1
]}

Dan, David ^{[1
]}

Jones, Zachary R. ^{[1
]}

Kozimor, Stosh A. ^{[1
]}

Mason, Harris E. ^{[1
]}

Meyer, Rachel L. ^{[1
,2
]}

Thiele, Nikki A. ^{[3
]}

Yang, Ping ^{[1
]}

Yuan, Mingbin ^{[1
]}

机构：

[1] Los Alamos Natl Lab, Los Alamos, NM 87545 USA

[2] Univ Rochester, Dept Chem Engn, Rochester, NY 14627 USA

[3] Oak Ridge Natl Lab, Chem Sci Div, Oak Ridge, TN 37831 USA

来源：

SCIENCE ADVANCES | 2024年 / 10卷 / 01期

关键词：

METAL-COMPLEXES; CATALYSTS; ISOTOPES; ELEMENTS; EXCHANGE; ETHERS; ENERGY; RADIUM; AMINES; IMPACT;

D O I：

10.1126/sciadv.adj8765

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Numerous technologies-with catalytic, therapeutic, and diagnostic applications-would benefit from improved chelation strategies for heavy alkaline earth elements: Ra2+, Ba2+, and Sr2+. Unfortunately, chelating these metals is challenging because of their large size and weak polarizing power. We found 18-crown-6-tetracarboxylic acid (H4COCO) bound Ra2+, Ba2+, and Sr2+ to form M(HxCOCO)(x-2). Upon isolating radioactive Ra-223 from its parent radionuclides (Ac-227 and Th-227), Ra-223(2+) reacted with the fully deprotonated COCO4- chelator to generate Ra(COCO)(2-)((aq)) (log KRa(COCO)2- = 5.97 +/- 0.01), a rare example of a molecular radium complex. Comparative analyses with Sr2+ and Ba2+ congeners informed on what attributes engendered success in heavy alkaline earth complexation. Chelators with high negative charge [-4 for Ra(COCO)(2-)((aq))] and many donor atoms [>= 11 in Ra(COCO)(2-)((aq))] provided a framework for stable complex formation. These conditions achieved steric saturation and overcame the weak polarization powers associated with these large dicationic metals.

引用

页数：14

共 76 条

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