Generation and Reactions of o-Bromophenyllithium without Benzyne Formation Using a Microreactor

• Published in: Journal of the American Chemical Society Vol. 129; no. 11; pp. 3046 - 3047
• Main Authors: Usutani, Hirotsugu, Tomida, Yutaka, Nagaki, Aiichiro, Okamoto, Hideho, Nokami, Toshiki, Yoshida, Jun-ichi
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 21.03.2007; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Multidisciplinary; Physical Sciences; Science & Technology; FLOW SYSTEM; MAGNESIUM EXCHANGE-REACTION; MICROSYSTEMS; MICRO REACTORS; CHEMISTRY; POLYMERIZATION; CATALYST; AROMATIC-COMPOUNDS; PRINCIPLES
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja068330s

Microflow systems were found to serve as powerful tools for mechanistic studies on reactions involving highly unstable intermediates such as o-bromophenyllithium, which is known to decompose to benzyne very quickly even at −78 °C. Precise residence time control and precise temperature control of microsystems are responsible. Based on the information thus obtained, the Br−Li exchange reaction of o-dibromobenzene followed by reactions with electrophiles without benzyne formation was achieved using a microflow system. Sequential use of two bromine atoms in o-dibromobenzene with Br−Li exchange reactions followed by the reactions with electrophiles using the microsystem consisting of four micromixers and four microtube reactors was also accomplished.