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Contents Vol 66(2)

Generation and Reactions of Pyridyllithiums via Br/Li Exchange Reactions Using Continuous Flow Microreactor Systems

Aiichiro Nagaki A , Daisuke Yamada A , Shigeyuki Yamada A , Masatomo Doi A , Daisuke Ichinari A , Yutaka Tomida A , Naofumi Takabayashi A and Jun-ichi Yoshida A B
+ Author Affiliations
- Author Affiliations

A Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.

B Corresponding author. Email: yoshida@sbchem.kyoto-u.ac.jp

Australian Journal of Chemistry 66(2) 199-207 https://doi.org/10.1071/CH12440
Submitted: 25 September 2012  Accepted: 28 November 2012   Published: 9 January 2013

Abstract

A continuous flow microreactor method for generating and carrying out reactions on pyridyllithiums has been developed based on Br/Li exchange reactions of bromopyridines and dibromopyridines. The reactions can be carried out without using cryogenic conditions by virtue of short residence times and efficient heat transfer, while very low temperatures such as –78 or –110°C are required for conventional batch macro methods. Moreover, sequential introduction of two different electrophiles has been successfully achieved using dibromopyridines in an integrated flow microreactor system composed of four micromixers and four microtube reactors.


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