Abstract: Preparation of chlorinating reagent or chlorination reaction itself for use in a reaction such as production of high intensity sweetener trichlorogalactosucrose (TGS) from partially protected sucrose, comprising reaction of dimethylformamide (DMF) with thionyl chloride or another sulphur containing inorganic acid chlorides including sulphuryl chloride is faced with a problem of prolific release of gaseous by-products, that at times may lead to violent explosion also. This problem is solved by innovative addition of solid powder inert to the constituents of the chlorination reaction mixture to the reaction, or by adding DMF to acid chloride solution in that order. The invention also leads to use of isolated solid Vilsmeier reagent being used for chlorination in a solvent other than DMF making it possible to avoid altogether problems arising from use of DMF which include irrecoverable loss in alkaline as well as acid conditions, interference in crystallization of TGS and the like.

Abstract: A process is described wherein after formation of first crop of Vilsmeier-Haack reagent by reacting Phosphorus Pentachloride with N,N-dimethylformamide to form a first crop of Vilsmeier reagent as insoluble crystals, a by-product of this reaction, the Phosphorus Oxy-Chloride, reacts with N,N-dimethylformamide to give a second crop of Vilsmeier reagent. This second crop of Vilsmeier reagent is soluble in DMF. This process makes it possible to double the yield of chlorinated substrate, such as sucrose-6-acetate or sucrose-6-benzoate, from the same quantity of Phosphorus Pentachloride.

Abstract: A method is disclosed for regioselective synthesis of sucrose-6-acetate via formation of a novel sucrose-tin adduct using sucrose and DBTO. The novel tin adduct can be represented by a formula (6-O-sucrose)-O—Snbutyl.sub.2-O-(6-O-sucrose) or as 1,3.(di O-sucrose) dibutyl stannylene. The adduct is acylated to yield sucrose-6-acetate or sucrose-6-benzoate as major product.