Learning Guide for Chapter 24 - Carboxylic Acid derivatives

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LG Ch 24 p 8Esters - C=O at 1735 cm -1C-O at 1000-1300 cm -1-1Amides - C=O at 1650 cmN-H 3200-3400 cm -1 (2 for primary, 1 for secondary, none for tertiary)NH 2 scissor sometimes overlaps C=ONitriles - triple bond at 2260-2200 cm -1NMR - protons on C's next to C=O's are around 2.0-2.5 ppm for all functional groupsprotons on C's next to O's are between 3-4 ppm in alcohols, ethers, and estersprotons on C's next to N's are between 2.5 and 3.0 for amines and amidesamide H's are variable, but usually appear between 5-8 ppm and exchange w/D 2 OH's on C=O's are about 9-11 ppm for aldehydes, 8 ppm for formic acid derivativesOOH 3 C C NONHOH NH 2
V. Hydrolysis of carboxylic acid derivativesLG Ch 24 p 9All carboxylic acid derivatives can be hydrolyzed to form carboxylic acids. The word"hydrolysis" comes from "hydro" meaning water and "lysis" meaning to cut, implyingthat these compounds are cut with water.Acid chlorides, anhydrides - react easily with water. Reactions involving these functionalgroups must be kept dry in order to avoid this side reaction. During the work-up thereaction is quenched with water and the acid chloride or anhydride undergoes hydrolysis.The mechanism for both of these reactions follows the typical pattern for carboxylic acidderivatives. The nucleophile attacks and the C=O electrons are pushed up; then theelectrons come back down and push off a chloride or carboxylate ion. A water moleculeor carboxylate ion then comes back and deprotonates the OH.OClHOHOOHOHOEsters, amides and nitriles do not simply react with water - they must be activated by acidin the presence of water or attacked by hydroxide in order to be hydrolyzed, and eitherreaction must be heated. Esters are the easiest to hydrolyze; amides require muchstronger acid or base, and nitriles likewise require strenous conditions.Esters - acid-catalyzed hydrolysis is the opposite of the Fischer esterification. It has anequilibrium constant near 1 and must be driven forward by using water as the solvent orremoval of the resulting alcohol.OOH 2 SO 4HOH
Page 1 and 2: Learning Guide for Chapter 24 - Car
Page 3 and 4: Esters can be formed from carboxyli
Page 5 and 6: LG Ch 24 p 5III. Nomenclature of ca
Page 7: 3-chloro-N-methylpentanamideN-benzy
Page 11 and 12: LG Ch 24 p 11Nitriles can be hydrol
Page 13 and 14: LG Ch 24 p 13If a mixed anhydride i
Page 15 and 16: LG Ch 24 p 15Acid chlorides can be
Page 17: LG Ch 24 p 17IX. Summary of reactio

Learning Guide for Chapter 24 - Carboxylic Acid derivatives

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