CARBOXYLIC ACIDS 507 (c) The phenyl and methyl substituents attached to C-2 of malonic acid play no role in the decar ①m OH dioxide 2-Phenylpropanoic acid 19.12 (b) The thermal decarboxylation of B-keto acids resembles that of substituted malonic acids. The structure of 2, 2-dimethylacetoacetic acid and the equation representing its decarboxylation were given in the text. The overall process involves the bonding H O CHaCCH(CH,) H,C H3 2. 2-Dimethylacetoacetic Enol form of 3-methy 3-Methyl-2-butanone 19.13 (a) Lactic acid(2-hydroxypropanoic acid) is a three-carbon carboxylic acid that bears a hydroxyl C-2. CH CHCOH 2-Hydroxypropanoic acid (b The parent name ethanoic acid tells us that the chain that includes the carboxylic acid func tion contains only two carbons. A hydroxyl group and a phenyl substituent are present at C-2. CHCO.H 2-Hydroxy-2-phenylethanoic acid (c) The parent alkane is tetradecane, which has an unbranched chain of 14 carbons. The termi- nal methyl group is transformed to a carboxyl function in tetradecanoic acid. Back Forward Main Menu TOC Study Guide Toc Student OLC MHHE Website(c) The phenyl and methyl substituents attached to C-2 of malonic acid play no role in the decar￾boxylation process. 19.12 (b) The thermal decarboxylation of -keto acids resembles that of substituted malonic acids. The structure of 2,2-dimethylacetoacetic acid and the equation representing its decarboxylation were given in the text. The overall process involves the bonding changes shown. 19.13 (a) Lactic acid (2-hydroxypropanoic acid) is a three-carbon carboxylic acid that bears a hydroxyl group at C-2. (b) The parent name ethanoic acid tells us that the chain that includes the carboxylic acid func￾tion contains only two carbons. A hydroxyl group and a phenyl substituent are present at C-2. (c) The parent alkane is tetradecane, which has an unbranched chain of 14 carbons. The termi￾nal methyl group is transformed to a carboxyl function in tetradecanoic acid. Tetradecanoic acid (myristic acid) CH3(CH2)12COH O 2-Hydroxy-2-phenylethanoic acid (mandelic acid) CHCO2H OH 2-Hydroxypropanoic acid CH3CHCO2H OH 3 21 Enol form of 3-methyl- 2-butanone C CH3 OH CH3C CH3 3-Methyl-2-butanone CH3CCH(CH3)2 O CO2 2,2-Dimethylacetoacetic acid O H C H3C CH3 O C O CH3C C CH3 O C OH O O C H heat  CO2 H3C C C OH OH CHCOH O CH3 2-Phenylpropanoic acid Carbon dioxide CARBOXYLIC ACIDS 507 __ __ __ Back Forward Main Menu TOC Study Guide TOC Student OLC MHHE Website