Interactions between Ketones and Alcohols: Rotational Spectrum and Internal Dynamics of the Acetone-Ethanol Complex
Qian Gou1, Laura B Favero2, Gang Feng1
1Department of Chemistry, College of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331, Chongqing, P. R. China.
Abstract:
The rotational spectra of two isotopologues of the 1:1 complex formed between acetone and ethanol have been recorded and analyzed by using Fourier-transform microwave spectroscopy. One rotamer was detected, in which ethanol adopts the gauche form. The two subunits are linked by a conventional O-H⋅⋅⋅O and a weak C-H⋅⋅⋅O hydrogen bond, forming a six-membered ring. Each rotational transition is split into five component lines due to the internal rotations of two nonequivalent acetone methyl groups. The V3 barriers to internal rotation of the two CH3 tops of acetone were determined to be 252(4) and 220(1) cm-1 , which are noticeably lower than the value for the monomer (266 cm-1 ).
Related Concept Videos
IR and UV–Vis Spectroscopy of Aldehydes and Ketones
Alkylation of β-Ketoester Enolates: Acetoacetic Ester Synthesis
Aldehydes and Ketones with Alcohols: Hemiacetal Formation
Types of Enols and Enolates
NMR Spectroscopy and Mass Spectrometry of Aldehydes and Ketones
Structures of Aldehydes and Ketones
In aldehydes (Figures 1a and 1b), the...


