b-cyclodextrin-controlled Reimer-Tiemann reaction for N,N-dimethylaniline

ORGN 399

Jigang Pan, School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan, 030006, China and Yuejun Huang, Department of Pharmacy, Shanxi Applied Bio-Technology College, Taiyuan, 030031, China.
Reimer-Tiemann Reaction is widely used for the formylation of phenols. Various phenolic aldehydes can be synthesized from phenols with chloroform – base reagents (dichlorocarbene) through Reimer-Tiemann reaction, while anilines are reacted with chloroform at basic conditions in relatively lower yields. Komiyama has demonstrated that the orientation of dichlorocarbene attack at phenolates was controlled by cyclodextrin. Primary and secondary amines easily reacted with dichlorocarbene first, due to their electron pair, to have isocyanate or N-formyl products, however, tertiary anilines, for example, N,N-dimethylaniline, are relative stable to these reactions. In this study, N,N-dimethylaniline was selected as a substrate for beta-cyclodextrin controlled Reimer-Tiemann reaction. Ratio of beta-cyclodextrin to N,N-dimethylaniline, potassium hydroxide concentration, addition methods, reaction time, solvent and temperature effects on the reaction were investigated and optimized. A reaction mechanism was proposed

 

Methodology, Synthesis, Asymmetric Reactions, Process R&D
8:00 PM-10:00 PM, Tuesday, March 25, 2003 Convention Center -- Hall G, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, March 24, 2003 Convention Center -- Hall G, Sci-Mix

Division of Organic Chemistry
The 225th ACS National Meeting, New Orleans, LA, March 23-27, 2003