CHIRAL LACTOLS .12. STUDIES ON THE ALDOLI ZATION OF GLYCOLALDEHYDE CATALYZED BY BASES

Base-catalyzed aldolization of the glycolaldehyde derivative 1 is stud ied under various reaction conditions. The resulting products, tetrose and hexose derivatives 2-11, are reduced to the corresponding sugar a lcohols and analyzed by HPL chromatography. All experiments leading to a trimerization of 1 give threose 3 as major product among the tetros es and allose 4 among the hexoses. An exception is the reaction cataly zed by LiOH, in which trimerization of 1 to the corresponding hexose d erivatives proceeds much slower and as products galactose 10 together with glucose 6 are favored above the other hexoses.