Question

Match the structures of compounds given in Column I with the classes of compounds given in Column If. Column-I Column-II (A) [X]C(C)C (P) Aryl halide (B) \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{X}\) (Q) Alkyl halide (R) Vinyl halide (S) Allyl halide

Short answer

The given compounds can be matched with their respective classes as follows: (A) -> (Q) Alkyl halide (B) -> (S) Allyl halide

Step-by-step solution

Analyze and Identify Functional Groups

First, let's analyze each compound from Column I and identify their functional groups: (A) [X]C(C)C This compound has a carbon atom bonded to X (halogen) and two other carbon atoms. (B) \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{X}\) This compound has a carbon-carbon double bond and a carbon atom bonded to X (halogen). Now, let's match them with the correct classes in Column II.

Matching with Classes in Column II

(A) [X]C(C)C The compound has a carbon atom bonded to X (halogen) and has other carbon atoms attached directly. As a carbon is bonded to three other carbons, this makes it an Alkyl halide. So, (A) matches with (Q). (B) \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{X}\) In this compound, the carbon atom bonded to the halogen is attached to a carbon that is part of a carbon-carbon double bond. Since it involves a carbon-carbon double bond with X (halogen) on the next carbon, this compound can be classified as an Allyl halide. So, (B) matches with (S). Final matching: (A) -> (Q) Alkyl halide (B) -> (S) Allyl halide

Key concepts

Functional Groups Identification

The identification of functional groups is a fundamental aspect of organic chemistry. Functional groups are specific atoms or groups of atoms within a molecule that are responsible for the characteristic chemical reactions of that molecule. In the context of the given exercise, the functional group in question is the halogen (represented by 'X') bonding to carbon atoms. Recognizing functional groups allows chemists to predict the reactivity of compounds and to classify them appropriately. For example, if a halogen is bonded to a carbon of an alkyl chain, the functional group is an alkyl halide. Whereas if it's attached to a carbon that's connected to a double bond, it's an allyl halide. Accurately identifying these groups not only aids in classifying compounds but also in understanding their behavior in chemical reactions.

Compound Classification

Compound classification involves grouping chemical compounds based on their structural features, and it is a critical step in the study of organic chemistry. Compounds can be categorized into various classes such as alcohols, ethers, ketones, and in this case, halides. Aryl, alkyl, vinyl, and allyl halides are differentiated based on the type of carbon that the halogen atom is attached to. Aryl halides have halogens bonded to aromatic rings, while alkyl halides feature halogens connected to saturated carbon chains. Distinguishing between these classes is vital for understanding their distinct properties and reactions.

Alkyl Halides

Alkyl halides, also known as haloalkanes, are compounds where a halogen (fluorine, chlorine, bromine or iodine) is bonded to an alkyl group (a saturated carbon chain). They are significant in chemical synthesis and have a variety of applications ranging from solvents to pharmaceuticals. The physical and chemical properties of alkyl halides depend on the halogen and the structure of the alkane. Simple alkyl halides like (A) in the exercise are primary if the halogen is attached to a carbon bonded to only one other carbon, secondary if bonded to two, and tertiary if bonded to three, as illustrated in the given solution.

Allyl Halides

Allyl halides are specialized alkyl halides wherein the halogen is bonded to a carbon atom that is adjacent to a carbon-carbon double bond (C=C). They are different from vinyl halides, where the halogen is directly attached to the double-bonded carbon. Compound (B) from the exercise exemplifies an allyl halide. These halides are particularly reactive due to the presence of the allylic system, which allows for unique pathways in organic reactions such as nucleophilic substitution and allylic oxidation. This reactivity is harnessed in various organic syntheses to create more complex molecules.