CH_3 CH_2 COCH_2 COCH_3 およびCH_3 CH_2 COCH_2 COCH_2 CH_3のラマン、赤外ならびにNMR スペクトル

摘要

2, 4-hexanedione should be expected to be of Cs for a rigid structure and be of C3v for a non-rigid one, and 3,5-h eptanedione should be expected to be of C3 or C2v for a rigid structure and be of D3d for a lnon-rigid one. However an exhaustive and unambiguous interpretation of the vibrational spectra of these β-diketone have not been achieved, and the obtained proton NMR spectra of 2,4-hexanedione and 3,5-heptanedione strongly support non-rigid models with the rotating CH2 and CO groups, respectively; C3v for 2, 4-hexanedione and D3d for 3,5-heptanedione.