美国国家加速器实验室T. J. A. Wolf团队报道了实时空间和时间中成像构象特定光化学。相关研究成果发表在2021年10月8日出版的国际学术期刊《科学》。

分子的构象异构体在生物学和有机化学中起着决定性的作用。然而，用于研究化学反应动力学的实验方法通常对构象不敏感。

研究人员报道了α-苯丙氨酸发生开环反应的气相兆伏超快电子衍射研究。研究人员在真实空间和时间内直接成像了一组特定的α-phellandrene构象演变成由Woodward-Hoffmann规则预测的产物异构体。该实验结果与非绝热量子分子动力学模拟结果在数量上是一致的，提供了构象如何影响光诱导开环反应的时间尺度和量子效率的相当详细的信息。

附：英文原文

Title: Conformer-specific photochemistry imaged in real space and time

Author: E. G. Champenois, D. M. Sanchez, J. Yang, J. P. Figueira Nunes, A. Attar, M. Centurion, R. Forbes, M. Gühr, K. Hegazy, F. Ji, S. K. Saha, Y. Liu, M.-F. Lin, D. Luo, B. Moore, X. Shen, M. R. Ware, X. J. Wang, T. J. Martínez, T. J. A. Wolf

Issue&Volume: 2021-10-08

Abstract: Conformational isomers (conformers) of molecules play a decisive role in biology and organic chemistry. However, experimental methods for investigating chemical reaction dynamics are typically not conformer-sensitive. We report on a gas-phase megaelectronvolt ultrafast electron diffraction investigation of α-phellandrene undergoing an electrocyclic ring-opening reaction. We directly imaged the evolution of a specific set of α-phellandrene conformers into the product isomer predicted by the Woodward-Hoffmann rules in real space and time. Our experimental results are in quantitative agreement with nonadiabatic quantum molecular dynamics simulations, which provide considerable detail of how conformation influences the time scale and quantum efficiency of photoinduced ring-opening reactions.

DOI: abk3132

Source: https://www.science.org/doi/10.1126/science.abk3132