Scholarlink

<p>Spontaneous symmetry breaking predominately occurs during the aggregation of discrete molecules in solution. Herein, we report a unique solid-state symmetry breaking process of dynamically chiral aza[4]helicenes that emerged in vacuum-driven transformation of halogen bond-woven crystals. Due to the weak feature of the halogen bonding, the halides in the cocrystals can be completely removed under vacuum at an elevated temperature. Interestingly, the aza[4]helicene molecules released from the halogen bond network solely adopt one chiral conformation upon reordering and symmetry breaking instantly occurs in a solid state. The Cotton effects gradually increase with the extension of vacuum–heating treatment, indicating a unidirectional transformation of the chiral conformations and an amplification of symmetry breaking during the solid-state reorganization. Moreover, the use of aza[6]helicene as a chiral inducer further enables a precise manipulation for the absolute configuration of the solid-state symmetry breaking, paving a distinctive route to chiral organic materials from achiral/racemic precursors.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Halogen bond-modulated solid-state reordering and symmetry breaking of azahelicenes

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年4月22日

查看全文
  • Juncong Liang,
  • Fuwei Gan,
  • Guoli Zhang,
  • Chengshuo Shen,
  • Huibin Qiu

摘要

Spontaneous symmetry breaking predominately occurs during the aggregation of discrete molecules in solution. Herein, we report a unique solid-state symmetry breaking process of dynamically chiral aza[4]helicenes that emerged in vacuum-driven transformation of halogen bond-woven crystals. Due to the weak feature of the halogen bonding, the halides in the cocrystals can be completely removed under vacuum at an elevated temperature. Interestingly, the aza[4]helicene molecules released from the halogen bond network solely adopt one chiral conformation upon reordering and symmetry breaking instantly occurs in a solid state. The Cotton effects gradually increase with the extension of vacuum–heating treatment, indicating a unidirectional transformation of the chiral conformations and an amplification of symmetry breaking during the solid-state reorganization. Moreover, the use of aza[6]helicene as a chiral inducer further enables a precise manipulation for the absolute configuration of the solid-state symmetry breaking, paving a distinctive route to chiral organic materials from achiral/racemic precursors.