CHEM 238 Exam 4 Questions Fully Solved Latest Update 2025 Graded A+

CHEM 238 Exam 4 Questions Fully Solved Latest Update 2025 Graded A+ What are acyl halides and how do you name them? - Answers carboxylic acid derivatives where the -OH is replaced by a halide named by replacing the previous -ic acid or -oic acid with the -oyl suffix, or by replacing the -carboxylic acid with -carbonyl, and then adding chloride or bromide, depending on the halide ex: acetyl chloride What are the 8 exceptions for an acyl halide where a -yl suffix is used rather than the -oyl suffix? - Answers For the following groups, the open ended connection is to the C=O carbon, and Cl can also be any halide formyl: -H acetyl: -CH3 propionyl: -CH2CH3 butyryl: -CH2CH2CH3 oxalyl: -COCl malonyl: -CH2COCL succinyl: -CH2CH2COCl glutaryl: -CH2CH2CH2COCl How do you name symmetrical and cyclic anhydrides? - Answers keep the -ic or -oic suffix, and replace "acid" with "anhydride How do you name unsymmetrical anhydrides? - Answers list the two acids with -ic or oic- suffixes alphabetically, and then add "anhydride" What is the structure for malonic anhydride, succinic anhydride, and glutaric anydride? - Answers a butane, pentane, and hexane ring, respectively, with a ketone on each side of the carbon thats replaced with an oxygen What is the structure for oxalic anhydride? - Answers a propane ring w 2 ketones and the other carbon replaced with an oxygen OR a hexane ring with 2 para carbons replaced by oxygen, and all other carbons having ketone attachments How do you name an ester? - Answers 1. Identify the alkyl group attached to the ether oxygen, this is the first word 2. Name the carboxylic acid derivative, replacing the -ic or -ioc suffix with an -ate suffix How do you name an amide with an unsubstituted -NH2 group? - Answers replace the -ic or -oic suffix with -amide, or replace "carboxylic acid" with "carboxamide" How do you name an amide with a substituent other than hydrogen on the nitrogen? - Answers place 1 or 2 N's at the beginning of the name depending on the level of substitution, and then list the substituents connected to the nitrogen, followed by the name of the acid ending in -amide or -carboxamide ex: N-methylpropanamide How do you name thioesters with common names? - Answers add the prefix thio- to the name of the carboxylate ex: acetate -> thioacetate How do you name esters with systematic names? - Answers the -oate or -carboxylate is replaced with a -thioate or -carbothioate What are the steric factors affecting carboxylic acid derivatives' reactivity? - Answers the more sterically hindered the carbonyl group is, the less reactive it is