There is disclosed a microchip reactor-type apparatus for effecting organic synthesis and reactions. The apparatus can be used in combination with many analytical instruments. The apparatus has a magnet for producing a static magnetic field for NMR measurements, a sample tube placed within the static magnetic field and holding a deuterated solvent therein, and a microchip reactor inserted inside the sample tube. A sample solution to be investigated is introduced into the channel formed in the microchip reactor while the microchip reactor is inserted inside the sample tube holding the deuterated solvent therein.