3.) Starting from phenol, the synthesis of 2,4-dichlorophenoxyacetic acid involves four steps outlined by the roadmap below. Please provide the missing reagents and products where necessary. HCl(aq) Cla FeCla OH 1. NaOH 2. OH 2,4-dichlorophenoxyacetic acid I

Provide the reagents necessary to carry out the following conversion.

Rank the following acids in decreasing acidity. Explain your answer   CH2ClCOOH, CHCl2COOH, CH3COOH

Do not give handwriting solution.

16-57 Starting with either benzene or toluene, how would you synthesize the following substances? Assume that ortho and para isomers can be separated. (a) 2-Bromo-4-nitrotoluene (c) 2,4,6-Tribromoaniline (b) 1,3,5-Trinitrobenzene (d) m-Fluorobenzoic acid

H₂C ཏཱཏི 1 ནི OH 1. Br2, PBг3 2. H₂O H3C OH Br The a-bromination of carbonyl compounds by Br2 in acetic acid is limited to aldehydes and ketones because acids, esters, and amides don't enolize to a sufficient extent. Carboxylic acids, however, can be a-brominated by first converting the carboxylic acid to an acid bromide by treatment with PBr3. Following enolization of the acid bromide, Br2 reacts in an a-substitution reaction. Hydrolysis of the acid bromide completes the reaction. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions :0: H3C Br Br + :::OH2 Br H₂O H3C Br за

Which combination of starting compounds should be chosen to prepare pentyl propanoate pentanoic acid and propanol pentanol and propanoic acid pentanol and pentanoic acid propanol and propanoic acid

Explain the differences in pKa (vs. benzoic acid) of these substituted benzoic acids based on fundamental chemical principles (not just what pKa means).

Arrange the following compounds in the increasing order of their acid strength: p-cresol, p-nitrophenol, phenol