EventsThe 13th International Electronic Conference on Synthetic Organic Chemistry
Event submissions
Published
with-doi10.3390/ecsoc-13-00199
This submission belongs to the session a. General Organic Synthesis of the event The 13th International Electronic Conference on Synthetic Organic Chemistry
Published date
31 Oct, 2009
Citation
Christian Rolando, Didier Barbry, Maël Penhoat, Cédric Kepka, Alkylation of substituted phenols in DMF by MeI using TMGN (bis- 1,1,8,8-(tetramethylguanidino)naphtalene) a proton sponge as base: a kinetics study by NMR spectroscopy, in Proceedings of The 13th International Electronic Conference on Synthetic Organic Chemistry, 1 November–30 November 2009, MDPI: Basel, Switzerland, doi: 10.3390/ecsoc-13-00199
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Alkylation of substituted phenols in DMF by MeI using TMGN (bis- 1,1,8,8-(tetramethylguanidino)naphtalene) a proton sponge as base: a kinetics study by NMR spectroscopy

Christian Rolando 1
Didier Barbry 1
Maël Penhoat 1
Cédric Kepka 1
1. Université de Lille 1, Sciences et Technologies, UMR CNRS USTL 8009, Organic and Macromolecular Chemistry, FR CNRS USTL 2638, Eugène-Michel CHEVREUL Institute, Villeneuve d’Ascq, France
Abstract
Evaluation of a new proton sponge, bis-1,1,8,8-(tetramethylguanidino)naphtalene (TMGN), in substituted phenols O-alkylation by methyl iodide in DMF has been studied. Kinetic measurements were performed in N,N-dimethylformamide-d7 and followed by 1H NMR using stoichiometric amounts of reagents. Plot of the results shows that the reaction follows an almost perfect second order rate law. However the Hammett plots for substituted phenols are not linear but bell shaped. In order to separate the deprotonation and alkylation contribution to the kinetics, deprotonation of phenols by TMGN has been investigated by quantitative 13C NMR. By combining these data a linear Hammett plot with a negative slope was obtained for the alkylation step and substituted phenol acidity constants in DMF, not accessible by NMR measurements, were determined which are in agreement with literature data.
Keywords
Alkylation of carboxylic acids in a microfluidic device: kinetics parameters determination, Hammett reaction constant measurement and optimization of preparative experiment
Ugi reactions of tertiary carboxylic acids: Combinatorial synthesis of glycyrrhetinic acid derivatives