Reactions between sucrose and esters of long chain fatty acids customarily have been conducted in a mutual solvent, such as dimethylformamide. The solvent‐free interesterification of molten sucrose and fatty acid esters at temperatures between 170–187 C has now been performed with the aid of lithium, sodium and potassium soaps as catalysts and solubilizers. When the reactants were heated rapidly and then subjected to reduced pressure, the interesterifications could be brought to equilibrium in 12 min or less, including the time necessary to melt the sucrose. The several soaps and combinations of soaps employed differed markedly in their performance. No sucrose esters were obtained with lithium palmitate, while the yield with lithium oleate was among the best, but consisted of over 90% tetra‐ and higher esters of sucrose. Lower esters were best produced with combinations of lithium oleate with sodium or potassium oleate employed at a level of about 25% total soaps, based on the weight of sucrose. The type of fatty acid ester employed also markedly affected the yield of sucrose esters. Among the esters tested, methyl carbitol palmitate (which could be formed in situ), monopalmitin, distearin and technical grade diglycerides (48% diglycerides) prepared from completely hydrogenated cottonseed oil, interesterified readily.

Thin tayer chromatography was adapted for direct quantitative estimation of sucrose esters of palmitic acid. Urea-phosphoric acid spray was used to detect the sucrose moiety of the various esters. The photometrically determined density of each spot on the thin layer plate was found to be proportional to its sucrose content. Ester content was then obtained by multiplying sucrose found by the factor, tool. wt. ester/mol, wt. sucrose. Ester mixtures were prepared by interesterifying sucrose with various proportions of methyl palmitate in dimettiylformamide solution. Positional isomers were observed at each level of substitution but could not be adequately separated from each other for quantitative evaluation.

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Sucrose palmitates were prepared by the interesterification of sucrose and methyl palmitate in different solvents. The ratio of methyl palmitate to sucrose in dimethylformamide (DMF) solution was varied so that the effect on yield and ester composition could be evaluated. When sucrose esters were prepared in DMF, the palmitoyl groups approximated a random distribution when only penta-and lower esters were formed. When the proportion of palmitoyl groups was increased, hexa-through octaesters were formed, but the yield was less than that calculated for a random distribution. The interesterification of sucrose and methyl palmitate in solvents other than DMF, but under otherwise identical reaction conditions, yielded different reaction products. Only traces of sucrose esters were produced in hexamethylphosphoramide and formylmorpholine. Reactions in dimethylsulfoxide and N-methyl-2-pyrrolidinone yielded larger percentages of higher esters than were obtained in DMF. However the distribution was far from random.