理论和实验力学研究水分子参与Prilezhaev反应
Eri Maeyama Kawahara1, Mitsuhiro Ogawa1, Shiho Yamato1
1Division of Materials Science, Graduate School of Science and Technology for Innovation, Yamaguchi, 7558611, Japan. sumimoto@yamaguchi-u.ac.jp.
Physical chemistry chemical physics : PCCP
|June 29, 2023
概括
水分子在普里莱沙耶夫反应中发挥着至关重要的作用,这是一个关键的环氧化物合成. 我们的研究表明,水直接参与反应机制,影响热力学参数.
科学领域:
- 有机化学 有机化学
- 反应机制 反应机制
- 计算化学计算化学
背景情况:
- 普里列谢耶夫反应是合成基和过氧酸的环氧化物的一个基本方法,通常使用m-chloroperoxybenzoic acid (mCPBA).
- 由于其爆炸性,商用mCPBA含有水,但水对Prilezhaev反应机制的影响在很大程度上尚未被探索.
- 了解水的作用对于优化环氧化物合成反应条件和产量至关重要.
研究的目的:
- 为了研究水在Prilezhaev反应中的机械作用.
- 在水的存在下,确定 styrene 和 mCPBA 之间的反应的热力学参数.
- 将实验数据与涉及不同机械路径的理论计算进行比较.
主要方法:
- 确定普里莱谢耶夫反应的热力学参数.
- 使用SMD和QM/MC/FEP方法计算激活自由能量,并纳入溶剂效应.
- 对协调机制与涉及水分子的机制进行计算参数的比较.
主要成果:
- 直接涉及两个水分子的反应机制的计算热力学参数与实验数据更好地一致.
- 协调机制的计算参数与实验结果不太一致.
- 这表明水在反应途径中起着重要作用.
结论:
- 水分子积极参与mCPBA介导的Prilezhaev反应的进展.
- 这些发现挑战了水性环境中纯粹协调机制的传统观点.
- 这项研究为Prilezhaev反应机制提供了关键的见解,特别是在使用商业mCPBA时.
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