Question

EXPERIMENT 20 CSI: SMU Part 2. Synthesis of an Ester. Esters are compounds of the form RCOOR'. They occur naturally in many plants and animals, and can be synthesized. They have a pleasant aroma usually described as "fruity of flowery". In a Fisher esterification an ester is formed from the reaction of a carboxylic acid and an alcohol with a strong acid as a catalyst. The OH contained in the carboxylic acid group 1s replaced with the alkoxy group (O-R") from the alcohol, and an ester and water are formed R-0-0-H + H-O-R = R-0-0-R' + H2O Questions Oil of Wintergreen: 1. Draw the chemical reaction between salicylic acid (the limiting reagent) and methanol. • Box the major functional group of each organic compound. • The formula of the catalyst is in the box above the reaction arrow. H.SO Salicylic acid + Methanol Methyl salicylate + Water catalyst Functional Group 2. What are two uses of methyl salicylate? Comment on the toxicity of methyl salicylate. What is considered a lethal dose, and what is its uptake avenue (inhalation, skin contact, ingestion, etc.)? 4. Why is the mixture reacted with a sodium bicarbonate solution? Write the reaction. It does NOT react with the limiting reagent since limiting reagents are completely consumed. 298

Answer 1

R hout. Ho-R & ROTHO Mechanism: no-HT IH-O-R OH W +H RH HR Locork HEB JI - H20 To-R R

cooH on 4. to for salicylic acid Methanel : CH₂OH. Mechanism: HONGO! Hon How do Ho-C OH CHOH OR CH3 or H. OH - Osca O-CH₂ HOLU HOT و همه Ho methyl salicylate
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