in benzene byproducts: H2O; reflux, 30 min; distg. off benzene and H2O, dissolving oily residue in Et2O, adding hexane, crystg. by placing in refrigerator overnight; elem. anal.;

in toluene byproducts: H2O; (inert atm.); mixture of tin compound and 2-hydroxybenzoic acid was reflux in toluene for 4-6 h with Dean-Stark apparatus, stand in room temp.; solvent evapd. in vac., recrystallized in chloroform/n-hexane (3:1), elem. anal.;

in benzene mixt. refluxed, resulting solid washed with petroleum ether; resulting solid washed with petroleum ether, dried under reduced pressure, elem. anal.;