Electrochemical Reduction of Benzaldehyde as its Girard-P Derivative at the Mercury Electrode and Differential-Pulse Polarographic Determination of Benzaldehyde

 The polarographic behaviour of benzaldehyde as its Girard-P derivative was studied using various electrochemical techniques and a method for the determination of benzaldehyde (10⁻⁶ − 8 × 10⁻⁵ M) by differential-pulse polarography, based on the in situ formation of its Girard-P derivative in aqueous solution at pH 2.5, is proposed. The relative standard deviation was 1.7% (ten determinations at the 5 × 10⁻⁵ M level). The applicability of this method is checked in benzyl alcohol and synthetic samples containing, o-aminophenol, 2-amino pyridine, o-cresol, amylic alcohol, salicylic acid, 4-aminobenzoic acid and naphthalene sulfonic acid. Received April 6, 2000. Revision February 13, 2001.