Exploring And Optimizing Systhesis Technology For The Sweetener-Sucralose

Sucralose is currently the most advanced highly intensity sweetener, produced by thesubstitution of chlorine atoms in the sucrose molecule in one of the five secondary hydroxylpositisions and two of the three primary hydroxyl positions. Sucralose has huge marketingpotential as its high sweetness, safety, good taste and so on.The key point to systhesis sucralose is to avoid the chlorination of the C-6positionwhich behaves high reactivity in the reaction. Based on the investigation of reportedsysthesis processes, this paper focused on the monoacetyl protection strategies which werewidely applied as its proceeding conveniently and moderately. The research work wastrying to explore and improve the process as the following aspects:1. Using dibutyltin oxide as the monoacetylation catalyst was limited as its toxicity onenvironment and human being. We tried to develop new catalysts such as organosiliconreagents to replace the organotin reagent in the monoacetyl protection strategy.2. Trimethyl orthoacetate was employed in over–dose campared to sucrose so that asatisfied purity of monoacetylation product could be abtained in the developed process toprepare sucralose. However this process would lead to higher costs due to the high price oftrimethyl orthoacetate. Herein we designed a new process based on the separation availablefor sucrose and sucrose4,6-orthoacylate. This new approach increased the purity ofmonoacylation products in the reaction solution under the condition that the excess amountof sucrose was employed, consequently reducing the costs. A recycle process for separatedsucrose was applied too. In this way, the utilization of trimethyl orthoacetate is up to almost90%.3. Detailed processing parameters had been discussed for each step.