Question

Draw the structure for each of the following organic halides: (a) dichloromethane (b) iodoethane (c) 2-fluoropropane (d) 1,2 -dibromopropane

Short answer

Dichloromethane: CH₂Cl₂; Iodoethane: C₂H₅I; 2-Fluoropropane: C₃H₇F; 1,2-Dibromopropane: C₃H₆Br₂.

Step-by-step solution

Understand Dichloromethane

The name 'dichloromethane' indicates that there are two chlorine (Cl) atoms attached to a methane structure. Methane (CH₄) serves as the base hydrocarbon. Replace two hydrogen atoms with chlorine atoms: the structure becomes CH₂Cl₂.

Draw Dichloromethane

Start with the methane structure (CH₄). Replace two hydrogen atoms with chlorine atoms. The structure is: H | Cl—C—Cl | H

Understand Iodoethane

'Iodoethane' is derived from ethane (C₂H₆), where one hydrogen atom is replaced with an iodine (I) atom. Therefore, its structure is C₂H₅I.

Draw Iodoethane

Begin with ethane (C₂H₆). Replace one hydrogen with an iodine atom. The resulting structure is: H H | | H—C—C—I | | H H

Understand 2-Fluoropropane

In '2-fluoropropane', the base structure is propane (C₃H₈), and a fluorine (F) atom replaces a hydrogen atom on the second carbon. The structure is C₃H₇F.

Draw 2-Fluoropropane

Start with propane (C₃H₈). Replace the hydrogen on the second carbon with fluorine. The structure is: H H H | | | H—C—C—C—H | | | F H

Understand 1,2-Dibromopropane

'1,2-dibromopropane' indicates that propane (C₃H₈) has two bromine atoms substituted for hydrogens at the first and second carbons. Thus, its formula is C₃H₆Br₂.

Draw 1,2-Dibromopropane

Start with propane (C₃H₈) and replace one hydrogen at the first and second carbon with bromine atoms. The structure is: Br Br | | H—C—C—C—H | | | H H H

Key concepts

Dichloromethane

Dichloromethane, also known as methylene chloride, is a simple organic halide with the chemical formula \( \text{CH}_2\text{Cl}_2 \). This molecule belongs to a class of compounds where halogen atoms are bonded to carbon atoms.

In dichloromethane, the carbon atom is at the center of the molecule, forming a tetrahedral geometry with four bonds. Two of these bonds are connected to hydrogen atoms, while the other two are replaced by chlorine atoms. Chlorine is a halogen, which is electronegative and thus pulls the electron density towards itself, creating dipole moments.

This compound is widely used as a solvent in applications ranging from paint stripping to the extraction process in the pharmaceutical industry. Because of its moderate polarity and volatility, dichloromethane is effective at dissolving a wide range of organic compounds. However, due care must be taken when handling it due to its potential health and environmental impacts.

• Main component: Methane (CH₄).
• Substituted elements: Two hydrogen atoms with chlorine atoms.
• Uses: Solvent in industrial processes.

Iodoethane

Iodoethane, commonly referred to as ethyl iodide, is an organic halide with the molecular formula \( \text{C}_2\text{H}_5\text{I} \). It is formed by replacing one hydrogen atom in ethane (\( \text{C}_2\text{H}_6 \)) with an iodine atom. This alteration gives iodoethane its unique properties.Iodine, being heavier and less electronegative compared to chlorine, significantly impacts the physical properties of iodoethane, such as its boiling point and reactivity. It often acts as an alkylating agent in organic synthesis, introducing the ethyl group into other compounds.

The linear structure of iodoethane allows it to interact with other molecules efficiently, thereby enhancing its functionality in chemical reactions. Due to the presence of iodine, proper handling and storage are essential to prevent degradation or hazardous reactions.

• Base structure: Ethane (C₂H₆).
• Modification: One hydrogen replaced with iodine.
• Reactivity: Acts as an alkylating agent.

Fluoropropane

Fluoropropane, specifically 2-fluoropropane, is an organic compound based on the alkane propane (\( \text{C}_3\text{H}_8 \)). In this molecule, a fluorine atom substitutes one hydrogen atom at the second carbon position, resulting in the chemical formula \( \text{C}_3\text{H}_7\text{F} \).

Fluorine, the most electronegative element, strongly influences the chemical properties of fluoropropane. It introduces a highly polar C-F bond, which has implications in its reactivity and interactions with other substances. Due to its structure, fluoropropane showcases higher stability compared to other halogenated alkanes.

This compound's stability makes it suitable for applications in fire extinguishing systems and as a refrigerant in various industries. It’s crucial to note that the positioning of fluorine on the second carbon contributes to specific steric and electronic characteristics that may influence its use in synthetic pathways.

• Base compound: Propane (C₃H₈).
• Fluorine placement: On the second carbon.
• Significance: High stability and specific uses in industries.

Dibromopropane

Dibromopropane, particularly 1,2-dibromopropane, is an organic compound derived from propane \( \text{C}_3\text{H}_8 \), featuring two bromine atoms substituting hydrogens at the first and second carbons of the chain. Its molecular formula is \( \text{C}_3\text{H}_6\text{Br}_2 \).

This halide is characterized by the introduction of two bromine atoms, which significantly affects its molecular interactions due to bromine's considerable size and moderate electronegativity. The dibrominated form results in increased molecular weight and a change in boiling point.

Dibromopropane is used primarily in organic synthesis as an intermediate agent, facilitating the formation of complex molecules. The placement of bromine at the first and second carbon atoms provides strategic interaction points, making it valuable for constructing specific molecular architectures.

• Based on: Propane (C₃H₈).
• Substitution pattern: Bromine on first and second carbons.
• Uses: Important in organic synthesis.