Carboxylic acids and derivatives (A-level only)

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Question 3
Medium

This question is about amino acids, peptides, and acylation reactions.

1.

Draw the structure of the zwitterion formed by serine, H2NCH(CH2OH)COOH\text{H}_2\text{NCH}(\text{CH}_2\text{OH})\text{COOH}H2​NCH(CH2​OH)COOH.

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2.

Draw the structure of phenylalanine, H2NCH(CH2C6H5)COOH\text{H}_2\text{NCH}(\text{CH}_2\text{C}_6\text{H}_5)\text{COOH}H2​NCH(CH2​C6​H5​)COOH, at high pH\text{pH}pH.

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3.

Draw the structures of both dipeptides formed when glycine, H2NCH2COOH\text{H}_2\text{NCH}_2\text{COOH}H2​NCH2​COOH, reacts with alanine, H2NCH(CH3)COOH\text{H}_2\text{NCH}(\text{CH}_3)\text{COOH}H2​NCH(CH3​)COOH. In each structure, show all the atoms and bonds in the amide (peptide) link.

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4.

An amide link is also formed when an acyl chloride reacts with a primary amine. Name and outline a mechanism for the reaction between propanoyl chloride, CH3CH2COCl\text{CH}_3\text{CH}_2\text{COCl}CH3​CH2​COCl, and ethanamine, CH3CH2NH2\text{CH}_3\text{CH}_2\text{NH}_2CH3​CH2​NH2​. Give the IUPAC name of the organic product.

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Carboxylic acids and derivatives (A-level only) Questions

  1. A Level
  2. /Chemistry
  3. /Carboxylic acids and derivatives (A-level only)