A complete and detailed mechanism for the reactions in Equation 18 − 15 is to be drawn. Concept introduction: If an aldehyde or ketone is treated with a large excess of an alcohol under acidic conditions, then the hemiacetal produced from nucleophilic addition reacts further to form an acetal, in which two alkoxy ( RO ) groups are bonded to the same carbon. The complete mechanism for this acetal formation reaction is shown in Equation 18 − 13 : The equation 18 − 15 is: The reversibility of acetal formation enables us to use acetals as protecting groups for ketones and aldehydes . Ketones and aldehydes are susceptible to an attack by nucleophiles (at the carbonyl carbon) and bases (at the α carbon), but acetals are inert to both strong nucleophiles and strong bases. One popular alcohol used to protect ketones and aldehydes is 1 , 2 − ethanediol (ethylene glycol), as shown in Equation 18 − 15 . 1 , 2 − ethanediol has two OH functional groups per molecule, so only one equivalent of the diol is needed. It also forms a five membered ring, which helps favor acetal formation.

Question

Want to see the full answer?

Answer 1

Question

Definition Definition Organic compounds that have a carbonyl group, C=O, as their functional group. The carbonyl group in aldehydes is placed at the end of the molecular structure, which means the C=O is attached to one hydrogen atom and an alkyl group or a benzene ring. Just like all the other homologous series in organic chemistry, the naming of aldehydes uses the suffix “-al”. The general molecular formula is C n H 2n O.

Chapter 18, Problem 18.8P

Interpretation Introduction

Interpretation:

A complete and detailed mechanism for the reactions in Equation 18−15 is to be drawn.

Concept introduction:

If an aldehyde or ketone is treated with a large excess of an alcohol under acidic conditions, then the hemiacetal produced from nucleophilic addition reacts further to form an acetal, in which two alkoxy (RO) groups are bonded to the same carbon. The complete mechanism for this acetal formation reaction is shown in Equation 18−13:

The equation 18−15 is:

The reversibility of acetal formation enables us to use acetals as protecting groups for ketones and aldehydes. Ketones and aldehydes are susceptible to an attack by nucleophiles (at the carbonyl carbon) and bases (at the α carbon), but acetals are inert to both strong nucleophiles and strong bases. One popular alcohol used to protect ketones and aldehydes is 1,2−ethanediol (ethylene glycol), as shown in Equation 18−15. 1,2−ethanediol has two OH functional groups per molecule, so only one equivalent of the diol is needed. It also forms a five membered ring, which helps favor acetal formation.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Students have asked these similar questions

Draw the complete, detailed mechanism for the following reaction.

Draw a detailed mechanism of the following reactions and determine the major product:

Draw a complete, detailed mechanism for this reaction.

Answer 2

Question

Definition Definition Organic compounds that have a carbonyl group, C=O, as their functional group. The carbonyl group in aldehydes is placed at the end of the molecular structure, which means the C=O is attached to one hydrogen atom and an alkyl group or a benzene ring. Just like all the other homologous series in organic chemistry, the naming of aldehydes uses the suffix “-al”. The general molecular formula is C n H 2n O.

Chapter 18, Problem 18.8P

Interpretation Introduction

Interpretation:

A complete and detailed mechanism for the reactions in Equation 18−15 is to be drawn.

Concept introduction:

If an aldehyde or ketone is treated with a large excess of an alcohol under acidic conditions, then the hemiacetal produced from nucleophilic addition reacts further to form an acetal, in which two alkoxy (RO) groups are bonded to the same carbon. The complete mechanism for this acetal formation reaction is shown in Equation 18−13:

The equation 18−15 is:

The reversibility of acetal formation enables us to use acetals as protecting groups for ketones and aldehydes. Ketones and aldehydes are susceptible to an attack by nucleophiles (at the carbonyl carbon) and bases (at the α carbon), but acetals are inert to both strong nucleophiles and strong bases. One popular alcohol used to protect ketones and aldehydes is 1,2−ethanediol (ethylene glycol), as shown in Equation 18−15. 1,2−ethanediol has two OH functional groups per molecule, so only one equivalent of the diol is needed. It also forms a five membered ring, which helps favor acetal formation.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 3

Question

Definition Definition Organic compounds that have a carbonyl group, C=O, as their functional group. The carbonyl group in aldehydes is placed at the end of the molecular structure, which means the C=O is attached to one hydrogen atom and an alkyl group or a benzene ring. Just like all the other homologous series in organic chemistry, the naming of aldehydes uses the suffix “-al”. The general molecular formula is C n H 2n O.

Chapter 18, Problem 18.8P

Interpretation Introduction

Interpretation:

A complete and detailed mechanism for the reactions in Equation 18−15 is to be drawn.

Concept introduction:

If an aldehyde or ketone is treated with a large excess of an alcohol under acidic conditions, then the hemiacetal produced from nucleophilic addition reacts further to form an acetal, in which two alkoxy (RO) groups are bonded to the same carbon. The complete mechanism for this acetal formation reaction is shown in Equation 18−13:

The equation 18−15 is:

The reversibility of acetal formation enables us to use acetals as protecting groups for ketones and aldehydes. Ketones and aldehydes are susceptible to an attack by nucleophiles (at the carbonyl carbon) and bases (at the α carbon), but acetals are inert to both strong nucleophiles and strong bases. One popular alcohol used to protect ketones and aldehydes is 1,2−ethanediol (ethylene glycol), as shown in Equation 18−15. 1,2−ethanediol has two OH functional groups per molecule, so only one equivalent of the diol is needed. It also forms a five membered ring, which helps favor acetal formation.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 4

Question

Definition Definition Organic compounds that have a carbonyl group, C=O, as their functional group. The carbonyl group in aldehydes is placed at the end of the molecular structure, which means the C=O is attached to one hydrogen atom and an alkyl group or a benzene ring. Just like all the other homologous series in organic chemistry, the naming of aldehydes uses the suffix “-al”. The general molecular formula is C n H 2n O.

Chapter 18, Problem 18.8P

Interpretation Introduction