Chapter 27.SE, Problem 20AP

Show the products you would expect to obtain from reaction of glyceryl Trioleate with the following reagents:

(a) Excess Br₂ in CH₂C_l2

(b) H₂/Pd

(c) NaOH/H₂O

(d) O₃, then Zn/CH₃CO₂H

(e) LiAlH₄, then H₃O₁

(f) CH₃MgBr, then H₃O₁

Interpretation Introduction

a) Excess Br₂ in CH₂Cl₂

Interpretation:

The product expected to be formed when glyceryl trioleate reacts with excess bromine in CH₂Cl₂ is to be given.

Concept introduction:

When compounds containing more than one olefinic double bond are treated with bromine in excess, addition of bromine to all the olefinic double bonds in the molecule takes place.

To give:

The product expected to be formed when glyceryl trioleate reacts with excess bromine in CH₂Cl₂.

Answer to Problem 20AP

The product expected to be formed when glyceryl trioleate reacts with excess bromine in CH₂Cl₂ is

Explanation of Solution

Glyceryl trioleate has three olefinic diuble bonds. When glyceryl trioleate is treated with excess bromine in CH₂Cl₂ addition of bromine takes place to all the three double bonds in the molecule.

Conclusion

The product expected to be formed when glyceryl trioleate reacts with excess bromine in CH₂Cl₂ is

Interpretation Introduction

b) H₂/Pd

Interpretation:

The product expected to be formed when glyceryl trioleate reacts with H₂/Pd is to be given.

Concept introduction:

When compounds containing more than one olefinic double bond are treated with H₂/Pd, reduction occurs and addition of hydrogen to all the double bonds in the molecule takes place.

To give:

The product expected to be formed when glyceryl trioleate reacts with H₂/Pd.

Answer to Problem 20AP

The product expected to be formed when glyceryl trioleate reacts with H₂/Pd is

Explanation of Solution

When glyceryl trioleate is treated with H₂/Pd, addition of hydrogen takes place to the three double bonds in the molecule to yield a saturated compound.

Conclusion

The product expected to be formed when glyceryl trioleate reacts with H₂/Pd is

Interpretation Introduction

c) NaOH/H₂O

Interpretation:

The products expected to be formed when glyceryl trioleate reacts with NaOH/H₂O are to be given.

Concept introduction:

When an oil or fat is treated with aqueous NaOH, the ester linkages in them get hydrolyzed to yield glycerol and sodium salt of the acid.

To give:

The products expected to be formed when glyceryl trioleate reacts with NaOH/H₂O.

Answer to Problem 20AP

The products expected to be formed when glyceryl trioleate reacts with NaOH/H₂O are given below.

Explanation of Solution

When glyceryl trioleate is treated with aqueous NaOH, the ester linkages in them get hydrolyzed to yield glycerol and sodium oleate.

Conclusion

The products expected to be formed when glyceryl trioleate reacts with NaOH/H₂O are given below.

Interpretation Introduction

d) O₃, then Zn/CH₃CO₂H

Interpretation:

The products expected to be formed when glyceryl trioleate reacts with O₃, then with Zn/CH₃COOH are to be given.

Concept introduction:

When a compound with double bond is treated with ozone and then with Zn/ CH3COOH, the double bond gets cleaved and the products have an oxygen atom attached to each carbon originally in the double bond.

To give:

The products expected to be formed when glyceryl trioleate reacts with O₃, then with Zn/CH₃COOH.

Answer to Problem 20AP

The products expected to be formed when glyceryl trioleate reacts with O₃, then with Zn/CH₃COOH are given below.

Explanation of Solution

When glyceryl trioleate is treated with O₃ and then with Zn/CH₃COOH, ozone adds to the three double bonds to yield a triozonide which is cleaved when treated with Zn/CH₃COOH to give two different aldehydes as products. The aldehyde carbons are present in a double bond in glyceryl trioleate.

Conclusion

The products expected to be formed when glyceryl trioleate reacts with O₃, then with Zn/CH₃COOH are given below.

Interpretation Introduction

e) LiAlH₄, then H₃O⁺

Interpretation:

The products expected to be formed when glyceryl trioleate reacts with LiAlH₄, then with H₃O⁺ are to be given.

Concept introduction:

When oils and fats are reduced with LiAlH₄, then with H₃O⁺, the eater linkages are reduced to give glycerol and the free acid. Double bonds are not reduced by LiAlH₄.

To give:

The products expected to be formed when glyceryl trioleate reacts with LiAlH₄, then with H₃O⁺.

Answer to Problem 20AP

The products expected to be formed when glyceryl trioleate reacts with LiAlH₄, then with H₃O⁺ are given below.

Explanation of Solution

When glyceryl trioleate is treated with LiAlH₄ and then with H₃O⁺ the ester linkages in it are reduced to alcohols. LiAlH₄ does not reduce the double bonds in glyceryl trioleate.

Conclusion

The products expected to be formed when glyceryl trioleate reacts with LiAlH₄, then with H₃O⁺ are given below.

Interpretation Introduction

f) CH₃MgBr, then H₃O⁺

Interpretation:

The products expected to be formed when glyceryl trioleate reacts with CH₃MgBr, then with H₃O⁺ are to be given.

Concept introduction:

Esters when treated with a Grignard reagent and then with H₃O⁺, react with two equivalents of the Grignard reagent to yield a tertiary alcohol. In oils and fats addition of Grignard reagent will take place to all the three carbonyl groups in the ester.

To give:

The products expected to be formed when glyceryl trioleate reacts with CH₃MgBr, then with H₃O⁺.

Answer to Problem 20AP

The products expected to be formed when glyceryl trioleate reacts with CH₃MgBr, then with H₃O⁺ are given below.

Explanation of Solution

When glyceryl trioleate is treated with CH₃MgBr, addition to carbonyl carbons takes place. The addition product when hydrolyzed with H₃O⁺ yields three equivalents of a tertiary alcohol and glycerol as products.

Conclusion

The products expected to be formed when glyceryl trioleate reacts with CH₃MgBr, then with H₃O⁺ are given below.