Step 3: If excess alcohol is present in the hemiacetal, the hemiacetal can be further converted to an acetal product, but only in the presence of acid. R₁ R₂ Why is acid required? R3OH, H+ HO OR3 R₁ R₂ hemiacetal R₂OH, H+ R30 R₁ OR3 acetal The alkoxy group in the hemiacetal must first be converted into a good leaving group. Acid stabilizes the hemiacetal, making it more reactive. Acid stabilizes the product. The hydroxy group in the hemiacetal must first be converted into a good leaving group. R₂ + H₂O

Step 3: If excess alcohol is present in the hemiacetal, the hemiacetal can be further converted to an acetal product, but only in the presence of acid. R₁ R₂ Why is acid required? R3OH, H+ HO OR3 R₁ R₂ hemiacetal R₂OH, H+ R30 R₁ OR3 acetal The alkoxy group in the hemiacetal must first be converted into a good leaving group. Acid stabilizes the hemiacetal, making it more reactive. Acid stabilizes the product. The hydroxy group in the hemiacetal must first be converted into a good leaving group. R₂ + H₂O

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter3: Organic Compounds: Alkanes And Their Stereochemistry

Section3.SE: Something Extra

Problem 49AP

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