Organic Chemistry : Help with Other Named Reactions

Study concepts, example questions & explanations for Organic Chemistry

varsity tutors app store varsity tutors android store

Example Questions

← Previous 1 3 4

Example Question #1 : Help With Other Named Reactions

 

 Wesag2o

Why does the reaction above require the use of Ag2O? 

Possible Answers:

The Ag2O attacks the alcohol to form the ether

The Ag2O is an inert solvent and allows the alcohol to attack and from the product without interference

The Ag2O oxidizes the alkyl halide to form the ether

The Ag2O reduces the alcohol to form the alkoxide ion

The Ag2O oxidizes the alcohol to form the alkoxide ion

Correct answer:

The Ag2O oxidizes the alcohol to form the alkoxide ion

Explanation:

The Ag2O oxidizes the alcohol to form the alkoxide ion. The Ag2O is a reducing agent, and it oxidizes the alcohol because the alcohol loses a proton. Ag2O is a strong base, meaning it will accept protons readily. The given reaction is an example of Williamson ether synthesis. This reaction occurs via an SN2 pathway. 

Example Question #2 : Help With Other Named Reactions

What is the IUPAC name of the following compound?

Untitled

Possible Answers:

3-bromo-2-methylcyclohexene

None of the other answers

2-bromo-1-methylcyclohexene

1-bromo-2-methyl-2-cycloxene

6-bromo-1-methylcyclohexene

Correct answer:

3-bromo-2-methylcyclohexene

Explanation:

The numbering of the molecule begins across the double bond and goes in the direction where the lowest numbers for substituents can be achieved. Thus, the methyl group will be on carbon two and the bromine on carbon 3. Substituents are ordered alphabetically. The base molecule is a six-membered ring with one double bond. This is called a cyclohexene.

Example Question #3 : Help With Other Named Reactions

What is the proper name of this molecule?

Untitled

Possible Answers:

E-2-ethyl-2-butene

Z-2-isohexene

E-3-methyl-2-pentene

None of the other answers

E-3-methyl-3-pentene

Correct answer:

E-3-methyl-2-pentene

Explanation:

The longest chain has five carbons and a double bond, so the base molecule is pentene. There is a methyl group on carbon 3. The double bond is between carbons two and three. The highest priority substituents are the ethyl group on one side and the methyl group on the other. One is up and one is down, so the molecule is E as opposed to Z.

Example Question #4 : Help With Other Named Reactions

Which of the following best summarizes the Michael reaction?

Possible Answers:

The enolate of an ester attacks another ester

A methyl ketone is treated with iodine and 

The enolate of a dicarbonyl compound attacks a beta carbon of an alkene

A carboxylic acid reacts first with then with water

An alkyl halide reacts first with the phthalimide ion, then with 

Correct answer:

The enolate of a dicarbonyl compound attacks a beta carbon of an alkene

Explanation:

The most acidic carbon in a dicarbonyl gets abstracted to form an enolate. The reaction involves a ketone with a double bond between the alpha and beta carbons. The carbon-carbon souble bond electrons attack the beta carbon of the alkene. At this point, the electrons from the alkene move to form a double bond between the carbonyl and alpha carbon and an enolate is fromed. The negative oxygen bonds to a hydrogen, forming the enol. Through enol-ketone tautamerization, a ketone is formed.

Example Question #5 : Help With Other Named Reactions

Which of the following best summarizes a Gabriel synthesis?

Possible Answers:

An alkyl halide reacts first with the phthalimide ion, then with

A carboxylic acid reacts first with then with water

The enolate of an ester attacks another ester

The enolate of a dicarbonyl compound attacks a beta carbon of an alkene

A methyl ketone is treated with iodine and

Correct answer:

An alkyl halide reacts first with the phthalimide ion, then with

Explanation:

An alkyl halide and phtalimide react under basic conditions to form a primary amine. The halogen leves and the nitrogen of the phtahlimide bonds to that carbon on the alkane. In the next step, the nitrogen leave the phthalimide. In the presence of base, the phthalimide gains two negative oxygens in the stead of the nitrogen. The final product is a primary amine. 

Example Question #6 : Help With Other Named Reactions

Last

For the given free radical halogenation reaction, which of the following is the product?

1.1

2. 2

3. 3

 4. 4

5. 5

Possible Answers:

2

Correct answer:

Explanation:

In a free radical halogenation, a bromine group will form a bond with the most substituted carbon atom. This method leads to the most stable radical intermediate.

Example Question #7 : Help With Other Named Reactions

Screen shot 2015 12 19 at 12.32.57 pm

Which of the following is the correct IUPAC name for the compound given?

Possible Answers:

2-methyl-4-ethylpentanal

2-ethyl-4-methylpentanal

2-ethyl-4-methylpentanal

2-methyl-4-hexanal

Correct answer:

2-ethyl-4-methylpentanal

Explanation:

The compound given has an aldehyde functional group and the parent chain has to have the -CHO group. Below is how the compound given should be numbered:

Screen shot 2015 12 20 at 9.45.33 pm

Aldehydes are named by changing the ending -e from the corresponding alkane with -al. The substituents on the parent chain should be named in alphabetical order. Therefore the answer is 2-ethyl-4-methylpentanal.

Example Question #8 : Help With Other Named Reactions

Screen shot 2015 12 19 at 12.45.00 pm

Which of the following is the correct IUPAC name for the compound given?

Possible Answers:

4-methyl-3-chlorolhexanol

4-chloro-3-methylhexanol

3-chloro-4-methylhexanol

4-chloro-6-hydroxy-3-methylhexane

Correct answer:

3-chloro-4-methylhexanol

Explanation:

The compound given has an alcohol functional group and the parent chain has to have the hydroxyl functional group. Below is how the compound given should be numbered:

Screen shot 2015 12 20 at 10.23.57 pm

Alcohols are named by changing the ending -e from the corresponding alkane with -ol. The substituents on the parent chain should be named in alphabetical order. Therefore the answer is 3-chloro-4-methylhexanol.

Example Question #9 : Help With Other Named Reactions

Screen shot 2015 12 20 at 10.03.53 pm

Which of the following is the correct IUPAC name for the compound given?

Possible Answers:

4-methy-4,5-dibromolhexane

4-methyl-2,3-dibromohexane

4,5-dibromo-4-methylhexane

2,3-dibromo-4-methylhexane

Correct answer:

2,3-dibromo-4-methylhexane

Explanation:

We have to find the longest chain to name it as the parent chain starting at the end with the nearest the substituent. Below is how the compound given should be numbered:

Screen shot 2015 12 20 at 10.05.59 pm

The substituents on the parent chain should be named in alphabetical order and because we have 2 bromine substituents we must add the name di-bromo and add the number of the carbon atom on the parent chain in which they appear. Therefore the answer is 2,3-dibromo-4-methylhexane.

Example Question #10 : Help With Other Named Reactions

Screen shot 2015 12 17 at 8.25.39 pm

Predict the product of the chemical reaction given.

Possible Answers:


Screen shot 2015 12 17 at 9.11.30 pm


Screen shot 2015 12 17 at 9.11.08 pm


Screen shot 2015 12 17 at 9.11.02 pm


Screen shot 2015 12 17 at 9.12.32 pm

Correct answer:


Screen shot 2015 12 17 at 9.11.08 pm

Explanation:

The reaction given is called a Fischer esterification reaction. It is a reaction between an alcohol and a carboxylic acid to form an ester. Carboxylic acids are not reactive enough to be attacked by an alcohol so the reaction requires a strong acid catalyst like hydrochloric acid for the reaction to occur. Below is the mechanism:


Screen shot 2015 12 17 at 9.31.18 pm

← Previous 1 3 4
Learning Tools by Varsity Tutors

Incompatible Browser

Please upgrade or download one of the following browsers to use Instant Tutoring: