Preparation of 2-Picolylarsonic Acid and its Reductive Cleavage by Ascorbic Acid/Iodine and by Thiophenol

Abstract

Contrary to dialkylaminoethyl halides, 2-picolyl chloride reacts with alkaline arsenite to give nearly quantitative yields 2-picolylarsonic acid. This acid is decomposed by ascorbic acid in the presence of catalytic amounts of iodine to 2-picoline and arsenious acid, most likely by hydride transfer from the ascorbic acid. Thiophenol decomposes this arsonic acid very quickly to 2-picoline, diphenyl disulfide and triphenyl trithioarsenite. In this case a proton from the thiophenol is transferred to the incipient 2-picolyl carbanion.

Keywords:

• 2-Picolyl Chloride
• Arsonic Acids
• Ascorbic Acid
• Dialkylaminoethyl Halides
• Picolylarsonic Acid
• The Meyer Reaction
• Thiophenol