Coupling Of Benzaldehyde Research Articles

One-Electron (2c/1e) Tin···Tin Bond Stabilized by ortho-Phenylenediamido Ligands.

Odd-electron bonds, i.e., the two-center, three-electron (2c/3e), or one-electron (2c/1e) bonds, have attracted tremendous interest owing to their novel bonding nature and radical properties. Herein, complex [K(THF)6][LSn:···Sn:L] (1), featuring the first and unsupported 2c/1e Sn···Sn σ-bond with a long distance (3.2155(9) Å), was synthesized by reduction of stannylene [LSn:] (L = N,N-dpp-o-phenylene diamide) with KC8. The one-electron Sn-Sn bond in 1 was confirmed by the crystal structure, DFT calculations, EPR spectroscopy, and reactivity studies. This compound can be viewed as a stabilized radical by delocalizing to two metal centers and can readily mediate radical reactions such as C-C coupling of benzaldehyde.

DFT Mechanistic Investigation on Manganese Pincer Complex Catalysed Cross-Coupling of Methanol with Benzyl Alcohol to Afford Methyl Benzoate.

In this paper the density functional theory (DFT) method was employed to investigate the cross-coupling of methanol with benzyl alcohol to afford methyl benzoate, catalysed by Mn-PNN pincer complex. The whole reaction process mainly includes three stages: the dehydrogenation of benzyl alcohol to benzaldehyde, the coupling of benzaldehyde with methanol to hemiacetal and the dehydrogenation of hemiacetal to methyl benzoate. The calculated results indicated that two dehydrogenation processes are influenced by two competitive mechanisms of inner and outer spheres. Dehydrogenation of benzyl alcohol to benzaldehyde is the rate-determining step of the whole reaction, with the energy barrier of 22.1 kcal/mol. In addition, the regeneration of catalyst is also extremely important. Compared with direct dehydrogenation, the dehydrogenation mode assisted by formic acid is more advantageous. This work might provide theoretical insights and shed light on the design of cheap transition-metal catalysts for the dehydrogenation reaction.

Electroreductive C[sbnd]O coupling of benzaldehyde over SACs Au–NiMn2O4 spinel synergetic composites

Electroreductive CO coupling provides a prospective strategy for biomass derivative upgrading via reducing the number of oxygen-containing functional groups and increasing their molecular weight. However, exploring superior electrocatalysts with effective reactivity and high selectivity for target products are still a challenge. In this work, single atom Au surface derived NiMn2O4 (SACs Au−NiMn2O4) spinel synergetic composites were fabricated by a versatile adsorption-deposition method and applied in electroreductive self-coupling of benzaldehyde to dibenzyl ether. The SACs Au–NiMn2O4 spinel synergetic composites enhanced electroreductive coupling of benzaldehyde, significantly improved the yield and selectivity of dibenzyl ether. Systematic characterizations and density functional theory calculation revealed that atomically dispersed Au occupied surface Ni2+ vacancies, which played a dominated role in CO coupling of benzaldehyde. Detailed calculation results showed that benzaldehyde preferred to adsorb on Ni octa-hedral sites of NiMn2O4 spinel synergetic structure, single atom Au surficial derivation over NiMn2O4 further reduced the adsorption energy (Eads) of benzaldehyde on SACs Au−NiMn2O4, thus the CO coupling of benzaldehyde to dibenzyl ether was promoted. Moreover, single atom Au surficial derivation lowered the energy barrier of rate-determining step, facilitated the formation of dibenzyl ether species. Our work also paves an avenue for rational design single atom materials using spinel as support.

Copper(II) chelate-bonded magnetite nanoparticles: A new magnetically retrievable catalyst for the synthesis of propargylamines

In this study, we document the use of a reusable magnetic nanoparticle (MNP)-supported copper catalyst for the efficient synthesis of propargylamines via the A 3 coupling of benzaldehydes, phenylacetylene, and piperidine or morpholine. The new MNPs were characterized by scanning electron microscopy, energy dispersive X-ray analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, and vibrating sample magnetometry. Notably, the activity and leaching test of the catalyst indicated that the MNPs could be reused without loss to its catalytic activity or leaching of its copper ligands.

Copper nanoparticles supported on graphene as an efficient catalyst for A3coupling of benzaldehydes

Cu nanoparticles (NPs) supported on graphene (G) obtained by pyrolysis of alginate is a highly active catalyst for the A3coupling of aldehydes, secondary amines and terminal acetylenes.

ChemInform Abstract: Terpenyl Selenides: Synthesis and Application in Asymmetric Epoxidation.

AbstractThe asymmetric base‐promoted coupling of benzaldehyde and benzyl bromide to 1,2‐diphenyloxirane is investigated in the presence of a variety (24 examples) of terpene derived selenides as chiral mediator or catalyst.

Tungstophosphoric Acid–Catalyzed Imino-Diels–Alder Reaction: An Efficient One-Pot Synthesis of Pyrano- and Furanoquinoline Derivatives

Tungstophosphoric acid has been found to be an efficient catalyst for the synthesis of pyranos- and furanoquinolines through the Imino-Diels–Alder reaction involving one-pot coupling of benzaldehydes, anilines, and 3,4-dihydro-2 H-pyran or 2,3-dihydrofuran. The products are formed at room temperature in excellent yields in a short period of time.