Effects of methylation in acceptors on the hydrogen bond complexes between 2,2,2-trifluoroethanol and cyclic ethers

Study of the Interactions between MeOH and Daidzein at the Molecular Level

In this study, the interactions between daidzein and methanol were studied to investigate isoflavone extraction. The complexes of MeOH-daidzein = 1:1, 2:1, 4:1, and 7:1 were studied using DFT/B3LYP-D3. According to the findings of this study, daidzein can act as a hydrogen bond donor as well as an acceptor. Binding energies demonstrate that more MeOH molecules interacting with daidzein could give more stability to the system. The strengths of the hydrogen bonds reveal that daidzein prefers to act as a hydrogen bond donor than an acceptor. The atoms in molecules (AIM) topological analysis was performed to analyze the nature of the hydrogen bonds. Moreover, daidzein, genistein, and glycitein are the most common soybean isoflavones, and their properties during extraction were also studied. The binding energies show that the soy isoflavone genistein is more reactive with the solvent than daidzein, followed by glycitein. The extraction conditions of the three common soy isoflavones in MeOH solution were obtained at 321, 328, and 348 K for genistein, daidzein, and glycitein, respectively. The generalized Kohn-Sham energy decomposition analysis (GKS-EDA) results indicate that the solute-solvent molecular interactions are typical hydrogen bonds with predominantly electrostatic and exchange energies in nature.

Molecular Understanding of Solvents and Glycitein Interaction during Extraction

Hydrogen bonding interaction plays a crucial role in liquid systems. Methanol, ethanol, and acetone are the most commonly used solvents to extract isoflavones from soybeans. The structural and electronic properties of the molecular clusters of naturally occurring glycitein with solvents were investigated using the density functional theory method employing the B3LYP-D3/cc-pVTZ approach. The influence of the solvent was carried out by using the polarized continuum model (PCM). The geometry optimization, vibrational frequencies, and topological parameters have been assessed at the same level of theory. From the molecular structure and thermodynamic point of view, the most stable structures are formed by the interaction between the carbonyl group of glycitein and MeOH or EtOH. For acetone-glycitein, the strongest interaction is formed by the interaction of the hydroxyl group of glycitein with the carbonyl group of acetone. All the hydrogen bonds in the MeOH/EtOH/acetone-glycitein complexes are closed-shell interactions. This study can help increase the efficiency of extraction.

Molecular interaction between MeOH and genistein during soy extraction

Genistein has received great attention due to its possible anti-oxidant properties. The interaction between genistein and the extraction solvent helps in understanding the extraction efficiency. Hydrogen bonding plays a crucial role in liquid systems. Density functional theory quantum chemical computations in both gas phase and solution were performed to investigate the molecular interaction between genistein and methanol. All the resulting complexes (MeOH : genistein = 1 : 1, 2 : 1, 3 : 1, 6 : 1) were studied using the B3LYP-D3 computational level and the cc-pVTZ basis set. Binding energies demonstrate that more MeOH molecules surrounding genistein could stabilize the system more. Geometry optimizations show that there are strong O–H⋯O interactions between MeOH and genistein. The electron density and the corresponding Laplacian of charge density at bond critical points were also calculated using AIM theory, and the results are in line with the structural and energetic analysis of the studied system. Moreover, energy decomposition analysis shows that the exchange energy term has the largest contribution to the attraction interaction energy as compared with other energy terms. Meanwhile, this study shows that the MeOH–genistein system is more stable under basic conditions. This study could help increase the efficiency of extraction.

The interaction between genistein and extraction solvent helps in understanding the extraction efficiency.