REAL-TIME MONITORING OF THE CATALYTIC-OXIDATION OF ALCOHOLS TO ALDEHYDES AND KETONES ON RESIN SUPPORT BY SINGLE-BEAD FOURIER-TRANSFORM INFRARED MICROSPECTROSCOPY

Catalytic oxidations of primary, benzylic, and secondary alcohols to a ldehydes and ketone using tetra-n-propylammonium perruthenate (TPAP) w ere carried out on resin supports for the first time. The reaction tim e course, percent conversion, and influence of catalyst amount have be en determined by analyzing IR spectra taken directly on a single resin bead in real time. Using 0.2 equiv of TPAP, a 92-97% conversion of al cohol to aldehyde or ketone has been achieved in 0.7-4 h based on the rates (rate constants (1.9 x 10(-4))-(2.5 x 10(-3)) s(-1)) of disappea rance and appearance of IR bands characteristic for alcohol, aldehyde, and ketone. The rapid adaptation of this oxidation method for solid-p hase synthesis demonstrates that single-bead FTIR microspectroscopy is a powerful method for facilitating the time-consuming reaction optimi zation stage of combinatorial chemistry.