2025年2月5日 · In situ DRIFTS analysis reveals that the cleavage of C Ar –OCH 3 bonds occurs preferentially over aromatic ring hydrogenation on the 1.5 nm Ru particles, minimizing side reactions and enhancing cyclohexanol selectivity.

1993年11月15日 · Using model calculations for a Cu 25 OCH 3 cluster the bonding interaction between the methoxy species and a Cu {111} surface has been investigated. In agreement with recent photoelectron diffraction measurements, OCH 3 is found to adsorb preferentially in the fcc three-fold hollow site with its O C axis perpendicular to the surface.

In the present study, the O-CH 3 bond dissociation enthalpies (BDEs) of 67 compounds belonging to phenol/anisole systems were calculated employing the Gaussian-4 (G4) method. Those compounds contain different substituents including alkyl groups, electron-donating groups (EDGs), and electron-withdrawing groups (EWGs).

1988年1月1日 · In the transition metal systems, standard bond distances were assumed for the OH, OCH3, SH, NH2, PH2, CH3, CN and SiH3 ligands, with HCH and HSiH bond angles of 109 and HNH or HPN angles of 120 Geometrical parameters for the Co(CO)4 fragment were those of the Co(CO)4- framework in HCo(CO)4.

2024年5月21日 · The high demethoxylation activity of SAC Pt/TiO2-H is mainly attributed to its weak hydrogen spillover capacity that suppressed the benzene ring hydrogenation and the deep deoxygenation. Additionally, SAC Pt/TiO2-H reduced the energy barrier of CAr–OCH3 bond cleavage and accordingly lowered the Gibbs free energy of the demethoxylation reaction.

In situ DRIFTS analysis reveals that the cleavage of C Ar –OCH 3 bonds occurs preferentially over aromatic ring hydrogenation on the 1.5 nm Ru particles, minimizing side reactions and enhancing cyclohexanol selectivity.

2020年4月2日 · For the O–CH 3 bond, electron-donating substituents enhance the ionic character of the O–CH 3 bond and the electron density on oxygen, shortening the O–CH 3 bond. In contrast, the phenyl–O bond is lengthened by electron-donating substituents and shortened by electron-withdrawing substituents.

In the present study, the O-CH3 bond dissociation enthalpies (BDEs) of 67 compounds belonging to phenol/anisole systems were calculated employing the Gaussian-4 (G4) method. Those compounds contain different substituents including alkyl groups, electron-donating groups (EDGs), and electron-withdrawing groups (EWGs).

The one-pot hydrodeoxygenation of lignin-derived (alkyl)-guaiacols to (alkyl)-cyclohexanols with high selectivity is an attractive process for biomass conversion. However, designing catalysts that preferentially cleave etheric C Ar –O(R) bonds over hydrogenating aromatic rings under mild conditions remains a significant challenge. In this ...

2018年10月20日 · Facts I know: 1) More the electron density in benzene ring, the faster the reaction. 2) Lone pair on -OCH3 group undergoes resonance and makes ortho-para positions electron rich, and so does -CH3 by hyperconjugation. 3) -OCH3 group shows -I (electron withdrawing) and -CH3 shows +I (electron releasing).