Mechanism insight into the cyanide-catalyzed benzoin condensation: a density functional theory study.

00:11 EST 24th November 2014 | BioPortfolio

Summary of "Mechanism insight into the cyanide-catalyzed benzoin condensation: a density functional theory study."

The reaction mechanism of the cyanide-catalyzed benzoin condensation without protonic solvent assistance has been studied computationally for the first time employing the density functional theory (B3LYP) method in conjunction with 6-31+G(d,p) basis set. Four possible pathways have been investigated. A new proposed pathway on the basis of the Lapworth mechanism is determined to be the dominant pathway in aprotic solvent, in which the formation of the Lapworth's cyanohydrin intermediate is a sequence including three steps assisted by benzaldehyde, clearly manifesting that the reaction can take place in aprotic solvents such as DMSO. In this favorable pathway with six possible transition states located along the potential energy surface, the reaction of the cyanide/benzaldehyde complex with another benzaldehyde to afford an alpha-hydroxy ether is the rate-determining dynamically with the activation free energy barrier of 26.9 kcal/mol, and the step to form cyanohydrin intermediate from alpha-hydroxy ether is partially rate-determining for its relatively significant barrier 20.0 kcal/mol.

Affiliation

College of Chemistry, Key Lab of Green Chemistry and Technology in Ministry of Education and State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610064, People's Republic of China.

Journal Details

This article was published in the following journal.

Name: The journal of physical chemistry. A
ISSN: 1520-5215
Pages: 9222-30

Links

PubMed Articles [12747 Associated PubMed Articles listed on BioPortfolio]

Palladium-Catalyzed Aza-Wittig-Type Condensation of Isoxazol-5(4H)-ones with Aldehydes.

This paper describes the development of a palladium-catalyzed decarboxylative inter- and intramolecular condensation reaction of isoxazol-5(4 H)-ones with carbonyl compounds in the presence of PPh3 ...

Unusual Reaction of NiFe-Hydrogenases with Cyanide.

Cyanide reacts rapidly with [NiFe]-hydrogenases (hydrogenase-1 and hydrogenase-2 from Escherichia coli) under mild oxidizing conditions, inhibiting the electrocatalytic oxidation of hydrogen as record...

An integration of condensation/Ullmann-type coupling/bicyclization sequences: copper-catalyzed three-component direct synthesis of 1,2,4triazolo1,5-bisoquinolin-5(1H)-ones.

A highly efficient three-component domino protocol has been developed for the synthesis of [1,2,4]triazolo[1,5-b]isoquinolin-5(1H)-ones from simple and readily available o-halogenated benzohydrazides,...

The inhibition of ribulose 1,5-bisphosphate carboxylase oxygenase by several 2-carboxyhexitol 1- and 6-phosphates.

The condensation of D-fructose 6-phosphate or 1-phosphate with cyanide has been used to synthesize 2-carboxyhexitol 6-phosphates and 1-phosphates. The products have been characterized in terms of thei...

U-CN versus Ce-NC Coordination in Trivalent Complexes Derived from MN(SiMe3)23 (M = Ce, U).

Reactions of [MN*3] (M = Ce, U; N* = N(SiMe3)2) and NR4CN (R = Me, Et, or (n)Bu) or KCN in the presence of 18-crown-6 afforded the series of cyanido-bridged dinuclear compounds [NEt4][(MN*3)2(μ-CN)] ...

Clinical Trials [1081 Associated Clinical Trials listed on BioPortfolio]

Is it Possible to Treat Cyanide Poisoning With HBO?

People who has been in a fire accident have been shown often to be cyanide poisoned as well as poisoned with carbon monoxide(CO). According to recommendations from the Danish Health Agency...

Mechanisms of Glucose Lowering Effect of Colesvelam HCl

The mechanism by which colesevelam HCl lowers glucose is not known. Knowledge of the potential mechanism of action is important for defining the role of the drug among oral antidiabetic a...

Bone Density of Newborn Infants to Mothers Treated With Selective Serotonin Reuptake Inhibitor (SSRI)

SSRI treatment in adults was found to decrease bone density. The use of SSRI among pregnant women with depression or anxiety is extendent and raising. The effect of bone density of the inf...

Characterization of Clonal B Cell Populations in HCV Infection

The purpose of this study is to investigate the mechanism of autoantibody production during chronic hepatitis C virus (HCV) infection. 10-50% of individuals with HCV have symptoms of mixed...

Reducing Energy Density by Different Methods to Decrease Energy Intake

The purpose of this research is to investigate how using different methods to reduce the energy density of entrees affects daily energy intake in adults. It is hypothesized that reducing t...

Medical and Biotech [MESH] Definitions

A white crystalline compound prepared by condensation of benzaldehyde in potassium cyanide and used in organic syntheses. This should not be confused with benzoin gum from STYRAX.

A plant genus in the LAURACEAE family. Lindera benzoin is a source of a balsamic resin called benzoin which is up to 1/3 BENZOIC ACID. This should not be confused with the chemical BENZOIN or the plant STYRAX BENZOIDES.

Hydrogen cyanide (HCN); A toxic liquid or colorless gas. It is found in the smoke of various tobacco products and released by combustion of nitrogen-containing organic materials.

Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

The amount of mineral per square centimeter of BONE. This is the definition used in clinical practice. Actual bone density would be expressed in grams per milliliter. It is most frequently measured by X-RAY ABSORPTIOMETRY or TOMOGRAPHY, X RAY COMPUTED. Bone density is an important predictor for OSTEOPOROSIS.

Search BioPortfolio:
Loading