高反応性部位が協調する、新たな低配位元素化学の開拓～2つの二価ゲルマニウム部位を炭素で架橋した分子の動的挙動と反応性～

2025-07-11 京都大学

＜関連情報＞

• https://www.kyoto-u.ac.jp/ja/research-news/2025-07-11
• https://www.kyoto-u.ac.jp/sites/default/files/2025-07/web_2507_Mizuhata-e5a263934344c88d019a600d2349fb32.pdf
• https://onlinelibrary.wiley.com/doi/10.1002/anie.202508927

メチレン架橋1,3-ビス(ゲルミレン)の二量体との動的平衡における反応性 Reactivity of a Methylene-Bridged 1,3-Bis(germylene) in Dynamic Equilibrium with Its Dimer

Daichi Uchida, Prof. Dr. Mariko Yukimoto, Prof. Dr. Norihiro Tokitoh, Prof. Dr. Mitsuaki Yamauchi, Dr. Hiroko Yamada, Prof. Dr. Yoshiyuki Mizuhata
Angewandte Chemie International Edition  Published: 23 June 2025
DOI:https://doi.org/10.1002/anie.202508927

Abstract

We report the properties and reactivity of an unprecedented methylene-bridged 1,3-bis(germylene) derivative. In the solid state, it undergoes dimerization to afford a 1,2,4,5-tetragermacyclohexa-1,4-diene derivative (Ge₄CHD). Moreover, theoretical calculations on Ge₄CHD reveal σ*–π interactions between the two π orbitals (Ge═Ge) and the CH σ* orbital. This interaction is confirmed by a significant red shift in the solid-state UV–vis spectrum. In contrast to the behavior in the solid state, the Ge₄CHD derivative dissociates in solution into a methylene-bridged 1,3-bis(germylene) derivative. The resultant 1,3-bis(germylene) derivative reacted with S₈ to form a novel cage compound containing three S and two Ge atoms. On the other hand, in the reaction with triphenylphosphine sulfide, the in situ generated 2-thia-1,3-digermabicyclo[1.1.0]butane derivative activated the benzene solvent, leading to the formation of a [2 + 2] cycloaddition product. Additionally, the 1,3-bis(germylene) derivative reacted with 4-dimethylaminopyridine (DMAP) to form a three-membered ring. Its structural parameters and the results of theoretical calculations indicated the zwitterionic character.