98888-86-9Relevant academic research and scientific papers
THE SYNTHESIS OF QUINOLINES FROM N-ALKYLFORMANILIDES AND ELECTRON-RICH ALKENES
Meth-Cohn, Otto
, p. 1901 - 1904 (1985)
N-Methylformanilide in phosphoryl chloride reacts with ketones, aldehydeand ketone enamines or enol acetates to give N-methylquinolinium salts in good yields.
The Reverse Vilsmeier Approach to the Synthesis of Quinolines, Quinolinium Salts and Quinolones
Meth-Cohn, Otto,Taylor, David L.
, p. 12869 - 12882 (2007/10/02)
N-Methylformanilide (MFA) reacts with various electron-rich alkenes in POCl3 solution to give N-methylquinolinium salts generally in good yield.The alkenes can be vinyl acetate, an aldehyde or ketone enamine (preferably the morpholine enamine), a methyl aryl ketone (reacting as its enol) or it may be generated from an alkanoamide bearing α-protons (which produces an α-chloroenamine in situ).The reaction is effective for a variety of other alkyl-, aryl- and benzyl-formanilides as well as ring substituted anilides though electron-withdrawing groups tend to inhibit cyclisation.The mechanism of the cyclisation has been elucidated and shown to involve an electrophilic ?6s process.The reactions of MFA with amides in POCl3 gives 4-quinolones on alkaline workup.
