Analytical Sciences

Abstract − Analytical Sciences, 23(4), 395 (2007).

Development of an NMR Interface Microchip “MICCS” for Direct Detection of Reaction Products and Intermediates of Micro-syntheses Using a “MICCS-NMR”
Yutaka TAKAHASHI,*1 Masamichi NAKAKOSHI,*2 Satoshi SAKURAI,*1 Yoshitake AKIYAMA,*3 Hiroto SUEMATSU,*1 Hiroaki UTSUMI,*1 and Takehiko KITAMORI*4
*1 Analytical Instrument Division, JEOL Ltd., 3-1-2 Musashino, Akishima, Tokyo 196-8558, Japan
*2 Instrumental Analysis Center, Yokohama National University, 79-1 Tokiwadai, Hodogaya, Yokohama, Kanagawa 240-8501, Japan
*3 Institute of Microchemical Technology Co., Ltd., 207 East KSP, Sakado, Takatsu, Kawasaki, Kanagawa 213-0012, Japan
*4 Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
The development of an NMR interface microchip and its applications to the real-time monitoring of chemical reactions are described. The microchip device was named “MICCS” (MIcro Channeled Cell for Synthesis monitoring), and the method using it was named “MICCS-NMR”. MICCS was inserted into a 5 mm Φ NMR sample tube. Thus standard solution NMR probes without any modifications can be used in MICCS-NMR measurements. A gap between MICCS and the sample tube was filled with a deuterated solvent for an NMR lock. The reaction temperature and reaction time in MICCS can be easily changed by adjusting the temperature of the NMR probe and changing the flow rates, respectively. The effectiveness of the MICCS-NMR was verified in the real-time monitoring of the Wittig reaction. Preliminary data on the direct detection of intermediates of the Grignard reaction is also reported. Besides real-time monitoring of chemical reactions, MICCS-NMR would be useful as a qualitative detection method for microchip-based synthesis.