Carbonyl Reactants - Organic Chemistry

In acidic solution, a hydrogen will be added to the hydroxy group of the given compound. This intermediate is a good leaving group. As it leaves, a hydrogen will be abstracted and a double bond will form. The bond is across carbons two and three becasue those two are more highly substituted than carbon 1, which is primary. The naming begins at the double bond, so the name is 4-bromo-2-hexene.

Chromic acid (formed in-situ via ), the correct answer, is a powerful oxidizing agent that converts primary alcohols to carboxylic acids. PCC is also an oxidizing agent, but oxidizes primary alcohols one "rung" up the ladder to aldehydes. , and are reducing agents, which react in the opposite direction of the given transformation.

The key to answering this question is to realize that potassium permanganate is a very powerful oxidizing agent. Therefore, the primary alcohol in the reactant will be completely oxidized into a carboxylic acid. It's also important to note that because potassium permanganate is such a powerful oxidizing agent, the primary alcohol will not just stop at the aldehyde level of oxidation, but will go all the way to a carboxylic acid, which is at the highest oxidation level.

or thionyl bromide is used to convert secondary alcohols to the bromide product as shown. Isopropyl alcohol is a secondary alcohol because the alcohol group is bonded to a carbon that is bonded to two other carbons.

The following reaction is the bromination of a secondary alcohol:

The correct answer is diethyl ether because this is the only ether compound listed.

Diethyl ether forms with the addition of a strong acid to ethanol.

In this question, we're being asked to identify which structure can be converted into an aldehyde in one step.

Now, let's remember what an aldehyde is. Aldehydes, along with ketones, are a carbonyl functional group. This means that it contains a carbon doubled bonded to an oxygen. But with aldehydes, the carbon-oxygen double bond is terminal. That is to say, it is at the end of the molecule, because the carbon atom is also bonded to at least one hydrogen atom.

In looking at the structures given in the answer choices, we see that most of them are alcohols. One of them is a ketone, which cannot be converted into an aldehyde in a single step, so this can be ruled out. For the other answer choices, we can see that we have a primary, secondary, and tertiary alcohol.

Due to the fact that aldehydes occur at the terminal position of a molecule, we know that if we were to start with an alcohol as our reactant, then it must be a primary alcohol. Thus, the only one that fits this is

Lithium aluminum hydride is a reducing agent. It reduces ketones and carboxylic acids to alcohols. 2-butanone is a 4-carbon chain with a double bond between an oxygen and carbon 2. The reduction turns the double bond with oxygen into a single bond to a hydroxy group. This makes the product 2-butanol.

This is a Grignard reagent carbon-carbon bond forming reaction. This reaction is being used with an ester which goes through a ketone intermediate with requires a second attack form the organolithium to reduce to an alcohol. Esters and acyl chlorides go to an alcohol with two of the same R groups from the organolithium in a Grignard reaction. This structure fits the bill:

In the presence of a strong base and benzene, ethylene glycol will convert ketones to acetals as seen in the product shown above. The given reagents will not react with esters or alcohols. The only given compound containing a ketone is molecule IV, the correct answer. This type of reaction is useful in organic synthesis when reaction at an ester is desired, but a ketone must be protected from reacting simultaneously. The acetal formed is often called a protecting group and may be reversed by addition of acid.

This question is asking what the most acidic hydrogen is in an aldehyde. To identify the most acidic hydrogen, we'll need to consider which conjugate base will be the most stable after the loss of hydrogen. When the alpha-hydrogen is lost, the resulting carbanion will be the most stabilized due to resonance with the adjacent carbonyl group. This resonance helps to distribute the negative charge on the carbanion over a greater area, which contributes to the greater stability of this conjugate base. Abstraction of a hydrogen from any of the other position would result in a carbanion that could not participate in resonance and thus would not be as stable.

LiAlH4 is a very strong reducing agent and it is a reactant that can reduce acyl chlorides into alcohols. There are 2 alcohols to choose from and now it needs to be known that LiAlH4 doesn't add anything but hydrogens to its substrate. (Note that in the correct answer, there is another H that is not drawn on the carbon bearing the hydroxyl group).

Below is the mechanism for the reaction given which is called the McMurry Reaction. It is a titanium (Ti) prompted pinacol coupling followed by deoxygenation.

Below is the mechanism for the reaction given which is called the McMurry Reaction. It is a titanium (Ti) prompted pinacol coupling followed by deoxygenation.

This reaction involves the generation of a radical by single electron transfer that couple through carbon-carbon bond formation to form the product pinacol. This reaction as shown below occurs in an aprotic solvlent:

It is extremely useful in organic synthesis to utilize methods by which less reactive carboxylic acids (and their derivatives) may be converted to more reactive species, like acid chlorides. Such reactions are not always intuitive as they proceed by transforming low-energy species to more energetic states. Reagents such as thionyl chloride and phosphorus tribromide , which you have likely seen previously in examination of common alcohol reactions, readily convert carboxylic acids to acid chlorides. The reaction is energetically favorable due to the formation of sulfur dioxide, a very stable gas.

A carboxylic acid can be synthesized directly into an acid anhydride by introducing the carboxylic acid to an acid chloride.

This question is asking us to determine what the product will be when a carboxylic acid is reacted with thionyl chloride, . In this reaction, the carboxylic acid is converted into an acyl chloride, with additional production of and as side products. Generally, this reaction is very useful for converting carboxylic acids into a more reactive form, so that further reactions can take place.

The Grignard reagent also acts as a base, and will remove any protons that have a low-enough pKa. This means that the alpha hydrogen will be removed, and the resulting carboxylate ion is stabilized through resonance and is unlikely to react with the protonated Grignard reagent.

This reaction is an acid-catalyzed esterification of a carboxylic acid. In the reaction the carbonyl is attacked by the alcohol oxygen, and the carbonyl is reformed by kicking off what was the hydroxyl group in the original carboxylic acid. What is left is an ester (of the form RCOOR', with R' containing the same number of carbons as was in the original alcohol).