Contents
How to Determine the Major Organic Product for the Reaction Scheme Shown
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Introduction
An important goal for organic chemists is to be able to predict the organic product that will result from a given reaction. This can be done by using the principles of Markovnikov’s rule and/or Constitutional isomers. In this guide, we’ll walk you through how to determine the major organic product for the reaction scheme shown below.
Methodology
In organic chemistry, it is often important to be able to predict the major organic product of a given reaction. This can be determined using the principle of microscopic reversibility. This principle states that the products of a reaction are the same whether the reaction proceeds forward or backward.
Identify the Major Product
The major product for the reaction scheme shown is determined by identifying the most stable carbocation. The stability of a carbocation is determined by its Hybridization, Inductive Effect, and Resonance Effect.
1) Determine the Hybridization of the carbocation.
2) Determine the Inductive Effect of groups on the carbocation.
3) Determine the Resonance Effect of groups on the carbocation.
The most important factor in determining the major product is the hybridization of the carbocation. The hybridization of a carbocation determines its shape, and therefore its stability. The most stable carbocation is a 3° Carbocation because it has a trigonal planar shape. The least stable carbocation is a 2° Carbocation because it has a linear shape. The intermediate stability belongs to 1° Carbocations, which have a triangular pyramid shape.
The inductive effect of groups also plays a role in determining the stability of a carbocation. Groups that are electron-donating will stabilize a carbocation while groups that are electron-withdrawing will destabilize a carbcation. For example, if we consider our reaction scheme above and look at group A, we see that it is an alkyl group (-CH3). Alkyl groups are electron-donating groups, so they will stabilize the 3° Carbocation that they are attached to. If we look at group B (H), we see that it is an electron-withdrawing group, so it will destabilize the 3° Carbocation that it is attached to.
The resonance effect of groups also affects the stability of a carbocation. We can draw two resonance structures for our 3° Carbocation above, which show that there are two ways to distribute electrons around the double bond:
Find the Reaction Scheme
In order to figure out the major organic product for the scheme shown, you will need to understand what it all means. The first step is finding the reaction scheme.
Use the Product Rule
In general, organic reactions can be divided into two categories: those that generate one product and those that generate multiple products. If you know the products of a reaction, it’s usually not too hard to write a balanced chemical equation. However, sometimes you will be asked to determine the major organic product for a given reaction scheme without being given the products. In order to do this, you need to use the product rule.
The product rule states that, in order for a reaction to occur, the reactants must come into contact with each other. This means that if there are multiple potential products, the one that is most likely to form is the one that has the least number of steps between the starting materials and the final product.
In order to apply this rule, you need to draw out all of the potential products and then count the number of steps between each reactant and each potential product. The reactant with the least number of steps to a given product is the one that is most likely to form that product in the reaction.
Use the Reaction Scheme
To determine the major organic product for the reaction scheme shown, we must first draw out the mechanism for the reaction.
The first step in the mechanism is the nucleophilic attack of water on the carbonyl carbon of propanal to form a oxonium ion intermediate. The second step is the loss of a proton from water to form a hydroxide ion, which then attacks the carbonyl carbon again to form an alcohol product. The final step is the loss of a proton from water to form a hydroxide ion, which then attacks the carbonyl carbon again to form an alcohol product.
The major organic product for this reaction scheme is thus propanol.
Results and Discussion
The following table lists the possible products of the reaction scheme. The products have been further classified as either major or minor. The major products are the ones that are most likely to be formed in the reaction, while the minor products are the ones that are less likely to be formed.
The Major Product
In order to determine the major organic product for the reaction scheme shown, we must first understand what factors influence the product distribution. The two main factors that contribute to this are the stability of the carbocation intermediate and the steric hindrance present in the reactants.
The stability of the carbocation intermediate is determined by its ability to rearrange to a more stable structure. In this reaction scheme, there are two potential rearrangements that could occur. The first is a 1,2-shift of the methyl group, and the second is a 1,2-shift of the ethyl group. Based on our knowledge of carbocation stability, we know that a methyl group is more stable than an ethyl group. Therefore, we can conclude that the major product will be formed via a 1,2-shift of the methyl group.
The second factor that contributes to product distribution is steric hindrance. When determining which product is favored, we must consider both reactants and products. In this reaction scheme, there is significant steric hindrance in both reactants and products. The presence of steric hindrance generally favors reactions that have fewer atoms in close proximity. Based on this information, we can conclude that the major product will be formed via a 1,2-shift of the methyl group because this results in fewer atoms in close proximity compared to the other potential product.
The Reaction Scheme
The Reaction Scheme
In the reaction scheme shown, there are four possible organic products that could be formed. In order to determine the major organic product, we must first draw the mechanism for the reaction.
The Product Rule
In organic chemistry, the product rule is a set of guidelines that allows chemists to predict the products of simple addition and elimination reactions. The product rule is based on the principle of microscopic reversibility, which states that a chemical reaction can be reversed if all of its reactants and products are present in the same proportions.
The product rule has three parts:
1) The identity of the reacting molecules (reactants) must be known.
2) The molecules must be arranged in such a way that they can collide with each other.
3) The collisions must have enough energy to overcome the attractive forces between the molecules (activation energy).
Assuming that these three conditions are met, the product rule can be used to predict the products of simple addition and elimination reactions.
The Reaction Scheme
The Reaction Scheme
In order to determine the major organic product for the reaction scheme shown, it is necessary to first identify the reactants and products. The reactants are shown on the left side of the reaction arrow, while the products are shown on the right side. In this case, the reactants are A and B, while the products are C and D.
Once the reactants and products have been identified, it is necessary to determine which of these species is the major organic product. This can be done by examination of the relative sizes of the reactant and product molecules. In general, the larger molecule will be the major organic product. In this case, molecule C is larger than molecule D, so it is likely that C is the major organic product.
To confirm that C is indeed the major organic product, it is necessary to examine the possible mechanisms by which this reaction could occur. The most likely mechanism involves a nucleophilic attack by species A on molecule B, followed by an elimination step to form molecule C. This mechanism is consistent with what is seen in other similar reactions, and so it is likely that this is indeed what occurs in this case.
Thus, we can conclude that molecule C is indeed the major organic product for this reaction scheme.
Conclusion
The major organic product for the reaction scheme shown is acetic acid.
