Electrochemical Determination of the pKa of Weak Acids in N,N-Dimethylformamide

Journal of the American Chemical Society

Volumn 113, Issue 24, 1991, Pages 9320-9329

  Maran, Flavio ^a   Celadon, Dino ^a   Severin, Maria Gabriella ^a   Vianello, Elio ^a  

^a UNIVERSITY OF PADOVA   (Italy)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001185584     PISSN: 00027863     EISSN: 15205126     Source Type: Journal    
DOI: 10.1021/ja00024a041     Document Type: Article

References (53)

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40. The fact that the reduction of α-bromo amides is affected to some degree by the mercury electrode was taken into consideration. Accordingly, we performed some explorative third peak measurements with bromo amide 3 using an inert electrode surface such as that provided by the glassy carbon electrode. With this electrode, the difference between the potential of the first and second peak is significantly reduced with respect to the behavior at mercury, in particular owing to a negative shift of the first peak. Nevertheless, the results obtained with mercury were reproduced within the experimental error. However, the use of glassy carbon is unpractical because the potential difference between the two main peaks must be as large as possible in order to have a third peak current unaffected by the foot of the second peak. We also performed some measurements with bromo amides 2 and 3 using tetra-butylammonium perchlorate in place of TEAP. Although the nature of the supporting electrolyte affects the positions of both peaks, the outcome of the measurements reported in Table III was not altered, at least within the overall error on pKa.
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