Trapping an Ester Hydrate Intermediate in a π-Stacked Macrocycle with Multiple Hydrogen Bonds

Bin Wang; Zi-Ang Nan; Qing Li; Jin Liu; Zi-Xiu Lu; Wei Wang; Zhu Zhuo; Guo-Ling Li; You-Gui Huang

doi:10.3390/molecules28155705

Trapping an Ester Hydrate Intermediate in a π-Stacked Macrocycle with Multiple Hydrogen Bonds

Molecules. 2023 Jul 28;28(15):5705. doi: 10.3390/molecules28155705.

Authors

Bin Wang^{1

2

3

4}, Zi-Ang Nan^{1

3}, Qing Li^{1

3}, Jin Liu^{1

3}, Zi-Xiu Lu^{1

3}, Wei Wang^{1

3}, Zhu Zhuo^{1

3}, Guo-Ling Li^{1

3}, You-Gui Huang^{1

2

3}

Affiliations

¹ CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China.
² Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou 350108, China.
³ Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institutes, Chinese Academy of Sciences, Xiamen 361021, China.
⁴ University of Chinese Academy of Sciences, Beijing 100049, China.

Abstract

Ester hydrates, as the intermediates of the esterification between acid and alcohol, are very short-lived and challenging to be trapped. Therefore, the crystal structures of ester hydrates have rarely been characterized. Herein, we present that the mono-deprotonated ester hydrates [CH₃OSO₂(OH)₂]^-, serving as the template for the self-assembly of a π-stacked boat-shaped macrocycle (CH₃OSO₂(OH)₂)_0.67(CH₃OSO₃)_1.33@{[ClLCo^II]₆}·Cl₄·13CH₃OH·9H₂O (1) (L = tris(2-benzimidazolylmethyl) amine), can be trapped in the host by multiple NH···O hydrogen bonds. In the solution of CoCl₂, L, and H₂SO₄ in MeOH, HSO₄^- reacts with MeOH, producing [CH₃OSO₃]^- via the ester hydrate intermediate of [CH₃OSO₃(OH)₂]^-. Both the product and the intermediate serve as the template directing the self-assembly of the π-stacked macrocycle, in which the short-lived ester hydrate is firmly trapped and stabilized, as revealed by single-crystal analysis.

Keywords: ester hydrate; hydrogen bonding; intermediate; self-assembly; π-stacking interaction.

Abstract

Grants and funding