Methyl Internal Rotation in Fruit Esters: Chain-Length Effect Observed in the Microwave Spectrum of Methyl Hexanoate.

ABSTRACT: The gas-phase structures of the fruit ester methyl hexanoate, CH₃-O-(C=O)-C₅H₁₁, have been determined using a combination of molecular jet Fourier-transform microwave spectroscopy and quantum chemistry. The microwave spectrum was measured in the frequency range of 3 to 23 GHz. Two conformers were assigned, one with C_s symmetry and the other with C₁ symmetry where the γ-carbon atom of the hexyl chain is in a gauche orientation in relation to the carbonyl bond. Splittings of all rotational lines into doublets were observed due to internal rotation of the methoxy methyl group CH₃-O, from which torsional barriers of 417 cm^-1 and 415 cm^-1, respectively, could be deduced. Rotational constants ob

SUBMITTER: Dang NN 

PROVIDER: S-EPMC9105109 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature