3. Formation of trichloroacetimidate donor 2,2,3,3'4',6,6'-Hepta-O-acetyl-ß-D-lactose trichloroacetimidate (3) Aco OAC О
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b) Write the reaction formula for this experiment
c) Give a full detailed mechanism (including curly arrows, by products, etc) for this experiment
3. Formation of trichloroacetimidate donor 2,2,3,3'4',6,6'-Hepta-O-acetyl-ß-D-lactose trichloroacetimidate (3) Aco OAC ОАс ОАс Асо Cl3CCN K2CO3 OAC Aco Nuoh DCM Aco -CCI3 OAC Aco OACACO OAC ОАс NH C26H36018 636.5532 C28H36C13NO 18 780.9403 Compound MW (g/mol) eq n (mmol) m (g) V (ml) d (g/ml) 636.55 1 104.71 Sugar (crude) Trichloroacetonitrile Potassium carbonate 8.5 1.44 144.39 138.21 3 DCM 84.93 1.33 Apparatus: 50 ml round bottom flask, N2 atmosphere Reaction temperature: RT Reaction time: TLC: EtoAc/Tol 1:1 + 1% NEtz Reaction molarity: 0.2 M The crude sugar is dissolved in dry DCM, trichloroacetonitrile and potassium carbonate are added. Stirring at RT until starting material is consumed. After complete conversion, the solution is filtered, concentrated in vacuo (water bath not warmer than 30 °C). Crude is used directly for next reaction.