Acridone studies. XIV. The selective demethylation of 2,3-Dimethoxy-10-methyl-9-oxoacridine-1,4-quinone by base

The selective demethylation of 2,3-dimethoxy-10-methyl-9-oxoacridine- 1,4-quinone by sodium hydroxide has been studied by following the change in product composition with hydroxide concentration, by measuring the relative extent of exchange at C2 and C3 with sodium methoxide[T], and by following the kinetics of the reaction in alkali. Reaction pathways are proposed to rationalize the observation that the C2 methoxyl group is replaced more readily in dilute alkali or on warming, but the C 3 methoxyl group is replaced in more concentrated alkali.

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Switching the reaction pathways of electrochemically generated β-haloalkoxysulfonium ions – synthesis of halohydrins and epoxides

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.11.27 ◽

2015 ◽

Vol 11 ◽

pp. 242-248 ◽

Cited By ~ 17

Author(s):

Akihiro Shimizu ◽

Ryutaro Hayashi ◽

Yosuke Ashikari ◽

Toshiki Nokami ◽

Jun-ichi Yoshida

Keyword(s):

Dimethyl Sulfoxide ◽

Sodium Hydroxide ◽

Sodium Methoxide ◽

Reaction Pathways ◽

Halocarbonyl Compounds

β-Haloalkoxysulfonium ions generated by the reaction of electrogenerated Br+ and I+ ions stabilized by dimethyl sulfoxide (DMSO) reacted with sodium hydroxide and sodium methoxide to give the corresponding halohydrins and epoxides, respectively, whereas the treatment with triethylamine gave α-halocarbonyl compounds.

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Estimation of Reaction Rates of Transesterification Pathways

Frontiers in Chemical Engineering ◽

10.3389/fceng.2021.673970 ◽

2021 ◽

Vol 3 ◽

Author(s):

Mario Alberto Pérez-Méndez ◽

Gladys Jiménez-García ◽

Rafael Huirache-Acuña ◽

Rafael Maya-Yescas

Keyword(s):

Sodium Hydroxide ◽

Fatty Acid Methyl Esters ◽

Reaction Rate ◽

Methyl Esters ◽

Reaction Rates ◽

Reaction Engineering ◽

Reaction Pathways ◽

Chemical Reactors ◽

Acid Methyl ◽

Kinetics Of

Experimental estimation of reaction rates is a common aspect of reaction engineering because reaction kinetics are the base of the design of chemical reactors. However, it is not easy to follow complex reactions as it is the case of transesterification of triglycerides in presence of sodium hydroxide. Identifying the possible reaction pathways taking place as ionic and sequential, starting with the inorganic formation of methoxide, and followed by each one of the three organic transesterification steps of virgin soybean oil, deeper understanding about kinetics of this reacting path has been obtained. Reaction rate evaluations were performed by following the solution’s pH, based on a 24–1 design of experiments, making possible to estimate the rate constants. Additionally, it was observed that there is an optimum amount of sodium hydroxide feed to the process, therefore it is possible to minimize its addition, which favors diminishing the volume of leaching water. The best yield to fatty acid methyl esters, using the minimum amount of sodium hydroxide, was 98.84 wt%, which is highly competitive.

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Kinetics of Substituted Bis- and Mono-azo Dyes as Corrosion Inhibitors for Aluminium in Hydrochloric Acid and Sodium Hydroxide Solutions

Journal of Chemical Research ◽

10.1177/174751989902300702 ◽

1999 ◽

Vol 23 (7) ◽

pp. 408-409

Author(s):

Loutfy H. Madkour ◽

R. M. Issa ◽

I. M. El-Ghrabawy

Keyword(s):

Hydrochloric Acid ◽

Sodium Hydroxide ◽

Azo Dyes ◽

Thermodynamic Model ◽

Corrosion Inhibitors ◽

Kinetics Of ◽

Alkaline Corrosion

This investigation is designed to apply an advanced kinetic–thermodynamic model on the data obtained from acidic and alkaline corrosion of aluminium using bis- and mono-azo dyes as corrosion inhibitors.

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