庚烷-2-酮的微波光谱和内旋转：气相中的信息素。

Microwave Spectrum and Internal Rotations of Heptan-2-one: A Pheromone in the Gas Phase.

机构信息

Institute of Physical Chemistry , RWTH Aachen University , Landoltweg 2 , D-52074 Aachen , Germany.

Institute Pierre Simon Laplace, CNRS UMR 7583, Université Paris-Est Créteil (UPEC), Université de Paris , Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA) , 61 avenue du Général de Gaulle , F-94010 Créteil , France.

出版信息

J Phys Chem A. 2020 Feb 20;124(7):1353-1361. doi: 10.1021/acs.jpca.9b11577. Epub 2020 Feb 7.

DOI:10.1021/acs.jpca.9b11577

PMID:31985229

Abstract

The microwave spectrum of heptan-2-one (CHCOCHCH) was recorded in the frequency range from 2 to 40 GHz using two molecular jet Fourier transform microwave spectrometers. The two energetically most favorable conformers could be identified and fitted with standard deviations close to measurement accuracy. The splittings arising from the internal rotations of two methyl groups, the acetyl methyl group CO- and the pentyl methyl group -CH, could be resolved. The barriers to internal rotation of the acetyl methyl group are 185.666(14) and 233.418(32) cm for conformer I and II, respectively, and can be linked to their specific geometries. For the pentyl methyl group, the respective barrier heights are 982.22(86) and 979.2(21) cm.

摘要

庚烷-2-酮（CHCOCHCH）的微波谱在 2 到 40GHz 的频率范围内使用两个分子喷射傅里叶变换微波光谱仪记录下来。可以识别出两种能量上最有利的构象，并将其拟合到接近测量精度的标准偏差范围内。可以分辨出两个甲基、乙酰甲基基团 CO-和戊基甲基基团 -CH 的内部旋转引起的分裂。乙酰甲基基团的内部旋转势垒分别为构象 I 和 II 的 185.666(14)和 233.418(32)cm，可以将其与它们的特定几何形状联系起来。对于戊基甲基基团，各自的势垒高度分别为 982.22(86)和 979.2(21)cm。