Chapter 29, Problem 29.28P

Draw the product formed when the following amino acid is treated with each reagent:

(a) ${\text{CH}}_{\text{3}}\text{OH}$, ${\text{H}}^{+}$; (b) ${\text{CH}}_{\text{3}}\text{COCl}$, pyridine; (c) $\text{HCl}$ ( $1$ equiv); (d) $\text{NaOH}$ ( $1$ equiv); (e) ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}\text{N}=\text{C}=\text{S}$.

Interpretation Introduction

(a)

Interpretation: The products formed by the treatment of given amino acid with ${\text{CH}}_{\text{3}}\text{OH,}{\text{H}}^{+}$ are to be drawn.

Concept introduction: The chemical compounds in which carbon is bonded with acidic and basic group along with hydrocarbon side chain are known as amino acids. The amine and carboxyl group of amino acid shows different reactions with alcohols, acid chloride, acid and base.

Answer to Problem 29.28P

The products formed by the treatment of given amino acid with ${\text{CH}}_{\text{3}}\text{OH,}{\text{H}}^{+}$ are,

Explanation of Solution

In the given ball-and-stick model of amino acid, the black balls represent carbon atoms, the white balls represent hydrogen atoms, the blue ball represents nitrogen atom and the red balls represent oxygen atoms. Therefore, the structure of given amino acid is,

Figure 1

The protection of carboxyl group takes place on reaction with ${\text{CH}}_{\text{3}}\text{OH,}{\text{H}}^{+}$ as shown in Figure 2.

Figure 2

Conclusion

The products formed by the treatment of given amino acid with ${\text{CH}}_{\text{3}}\text{OH,}{\text{H}}^{+}$ are shown in Figure 2.

Interpretation Introduction

(b)

Interpretation: The products formed by the treatment of given amino acid with ${\text{CH}}_{\text{3}}\text{COCl}$, pyridine are to be drawn.

Concept introduction: The chemical compounds in which carbon is bonded with acidic and basic group along with hydrocarbon side chain are known as amino acids. The amine and carboxyl group of amino acid shows different reactions with alcohols, acid chloride, acid and base.

Answer to Problem 29.28P

The products formed by the treatment of given amino acid with ${\text{CH}}_{\text{3}}\text{COCl}$, pyridine are,

Explanation of Solution

The structure of given amino acid is shown in Figure 1.

The amine group of amino acid form amide bond on reaction with acid chloride as shown in Figure 3.

Figure 3

Conclusion

The products formed by the treatment of given amino acid with ${\text{CH}}_{\text{3}}\text{COCl}$, pyridine are shown in Figure 3.

Interpretation Introduction

(c)

Interpretation: The products formed by the treatment of given amino acid with $\text{HCl}$ are to be drawn.

Concept introduction: The chemical compounds in which carbon is bonded with acidic and basic group along with hydrocarbon side chain are known as amino acids. The amine and carboxyl group of amino acid shows different reactions with alcohols, acid chloride, acid and base.

Answer to Problem 29.28P

The products formed by the treatment of given amino acid with $\text{HCl}$ are,

Explanation of Solution

The structure of given amino acid is shown in Figure 1.

The amine group of amino acid form amide bond on reaction with acid chloride as shown in Figure 4.

Figure 4

Conclusion

The products formed by the treatment of given amino acid with $\text{HCl}$ are shown in Figure 4.

Interpretation Introduction

(d)

Interpretation: The products formed by the treatment of given amino acid with $\text{NaOH}$ are to be drawn.

Concept introduction: The chemical compounds in which carbon is bonded with acidic and basic group along with hydrocarbon side chain are known as amino acids. The amine and carboxyl group of amino acid shows different reactions with alcohols, acid chloride, acid and base.

Answer to Problem 29.28P

The products formed by the treatment of given amino acid with $\text{NaOH}$ are,

Explanation of Solution

The structure of given amino acid is shown in Figure 1.

The amine group of amino acid form amide bond on reaction with acid chloride as shown in Figure 5.

Figure 5

Conclusion

The products formed by the treatment of given amino acid with $\text{NaOH}$ are shown in Figure 5.

Interpretation Introduction

(e)

Interpretation: The products formed by the treatment of given amino acid with ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}\text{N}=\text{C}=\text{S}$ are to be drawn.

Concept introduction: The chemical compounds in which carbon is bonded with acidic and basic group along with hydrocarbon side chain are known as amino acids. The amine and carboxyl group of amino acid shows different reactions with alcohols, acid chloride, acid and base.

Answer to Problem 29.28P

The products formed by the treatment of given amino acid with ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}\text{N}=\text{C}=\text{S}$ are,

Explanation of Solution

The structure of given amino acid is shown in Figure 1.

The terminal amine group of amino acid on reaction with phenyl isothiocyanate form N-phenylthiohydantoin as shown in Figure 6.

Figure 6

Conclusion

The products formed by the treatment of given amino acid with ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}\text{N}=\text{C}=\text{S}$ are shown in Figure 6.