What Is 1-Bromopropane

Content on WhatAnswers is provided "as is" for informational purposes. While we strive for accuracy, we make no guarantees. Content is AI-assisted and should not be used as professional advice.

Last updated: April 11, 2026

Quick Answer: 1-Bromopropane (C₃H₇Br) is a volatile, colorless liquid alkyl halide with CAS number 106-94-5, historically used as a solvent replacement for ozone-depleting substances but now restricted in many countries due to neurotoxicity concerns in occupational settings.

Key Facts

Chemical formula C₃H₇Br with molecular weight of 122.99 g/mol, boiling point of 71°C
Introduced as replacement for CFC-113 and other ozone-depleting solvents in the 1990s
Linked to serious neurological effects in workers, causing peripheral neuropathy and central nervous system damage
Banned by the EPA in the United States in 2020 and restricted in EU and other countries
Still used in some pharmaceutical manufacturing and laboratory applications despite health restrictions

Overview

1-Bromopropane (also known as n-propyl bromide or n-PrBr) is a colorless, volatile organic compound with the chemical formula C₃H₇Br. It is an alkyl halide belonging to the class of simple halogenated hydrocarbons, with a molecular weight of approximately 122.99 g/mol and a boiling point of 71°C. This flammable liquid has been widely used in industrial applications as a solvent and cleaning agent.

Originally promoted during the 1990s as an environmentally-friendly replacement for ozone-depleting substances like CFC-113 and other chlorofluorocarbons, 1-bromopropane was embraced by various industries including electronics manufacturing, aerospace, and dry cleaning. However, subsequent research revealed significant health and safety concerns that would eventually lead to strict regulations and bans in multiple countries. Today, its use is heavily restricted or prohibited in many jurisdictions, though some applications in pharmaceutical manufacturing and laboratory settings continue in regulated environments.

How It Works

1-Bromopropane functions as a solvent and degreasing agent through several key mechanisms:

Chemical Structure: As an alkyl halide, it contains a bromine atom attached to a three-carbon chain, giving it excellent solvent properties for dissolving oils, greases, and various organic compounds used in manufacturing.
Volatility and Evaporation: Its relatively low boiling point of 71°C enables rapid evaporation at room temperature, making it effective for quick-drying applications in cleaning and degreasing operations without leaving residue.
Nucleophilic Displacement: The bromine atom acts as a good leaving group, allowing 1-bromopropane to participate in organic chemistry reactions such as SN2 nucleophilic substitution reactions used in pharmaceutical and fine chemical synthesis.
Solvent Polarity: Despite being nonpolar, the compound has moderate dipole characteristics that allow it to dissolve both polar and nonpolar substances, making it versatile for industrial cleaning applications.

Key Comparisons

Property	1-Bromopropane	CFC-113 (Predecessor)	Modern Alternatives
Ozone Depletion Potential	Zero (no chlorine)	0.8 (high)	Zero
Health Hazard Classification	Neurotoxin (restricted)	Toxic	Varies by alternative
Boiling Point	71°C	47°C	40-150°C depending on type
Current Regulatory Status	Banned (EPA 2020)	Banned globally (Montreal Protocol)	Generally approved with restrictions
Primary Uses	Electronics, cleaning (now restricted)	Cleaning agent, solvent	Aqueous/bio-based cleaners, esters

Why It Matters

Occupational Health Concern: The primary significance of 1-bromopropane lies in its neurotoxic effects on workers. Exposure to this chemical has been associated with irreversible peripheral neuropathy, characterized by nerve damage in hands and feet, as well as central nervous system effects reported in manufacturing workers globally.
Environmental Policy Lesson: The rise and fall of 1-bromopropane demonstrates the importance of conducting comprehensive health and safety studies before replacing established chemicals. Its promotion as an eco-friendly alternative that later proved harmful has influenced how regulatory agencies now evaluate replacement chemicals.
Regulatory Evolution: The U.S. Environmental Protection Agency issued a final ban on 1-bromopropane in 2020, with phase-out requirements completed in 2024, representing significant regulatory action against an industrial chemical despite industry resistance.

Today, 1-bromopropane serves as a cautionary example in green chemistry and occupational health. Industries have shifted toward safer alternatives including aqueous-based cleaners, semi-aqueous solutions, and specialty esters that provide similar cleaning capabilities without the documented neurotoxic risks. Understanding the history and hazards of 1-bromopropane is essential for chemical safety professionals, regulatory bodies, and industries seeking to adopt new solvents responsibly.