1-Bromobutane is a colorless liquid organic compound with the molecular formula C4H9Br. It is used as an alkylating agent in organic synthesis and as a solvent in industry.
| IUPAC Name | Butyl bromide |
| Molecular Formula | C4H9Br |
| CAS Number | 109-65-9 |
| Synonyms | 1-Bromobutane, n-Butyl bromide, Butyl bromide, Bromobutane, Butane, 1-bromo-, 109-65-9, 1-brombutan, 1-bromobutane, n-C4H9Br |
| InChI | InChI=1S/C4H9Br/c1-2-3-4-5/h2-4H2,1H3 |
1-Bromobutane molar mass
The molar mass of 1-Bromobutane is 137.03 g/mol. To obtain the molar mass of 1-Bromobutane, one adds the atomic masses of carbon, hydrogen, and bromine in a single molecule. Chemical calculations often require the conversion of a substance’s mass to its number of moles, and the molar mass is essential for this conversion.
1-Bromobutane density g/ml
The density of 1-Bromobutane is 1.27 g/mL at 25 °C (77 °F). This is the mass per unit volume of the substance. The density of 1-Bromobutane is higher than that of water, which allows it to be easily separated from aqueous solutions.
1-Bromobutane boiling point
The boiling point of 1-Bromobutane is 101 °C (214 °F). This is the temperature at which the vapor pressure of the liquid equals the external pressure. It is a measure of the strength of intermolecular forces in the liquid. The boiling point of 1-Bromobutane makes it a useful solvent and reagent in organic chemistry.
C4H9Br melting point
The melting point of C4H9Br is -112 °C (-170 °F). This is the temperature at which the solid and liquid phases of the substance are in equilibrium. The melting point depends on the strength of intermolecular forces in the solid. The low melting point of C4H9Br makes it a liquid at room temperature and allows it to be easily handled.
C4H9Br molecular weight
The molecular weight of C4H9Br is 137.03 g/mol. This is the sum of the atomic weights of all the atoms in the molecule. The molecular weight is used to calculate the amount of a substance needed for a reaction or to determine the amount of product obtained.
1-Bromobutane structure
1-Bromobutane has a straight-chain alkyl structure with a bromine atom attached to the fourth carbon atom. It is an organic compound with the chemical formula C4H9Br. The structure of 1-Bromobutane determines its physical and chemical properties and its reactivity in organic reactions.
1-Bromobutane formula
The formula of 1-Bromobutane is C4H9Br. This shows the number and type of atoms present in the molecule. The formula of 1-Bromobutane is important in determining its reactivity and behavior in chemical reactions.
| Appearance | Colorless liquid |
| Specific Gravity | 1.27 at 25°C |
| Color | Colorless |
| Odor | Characteristic, sweet odor |
| Molar Mass | 137.03 g/mol |
| Density | 1.27 g/mL at 25°C |
| Melting Point | -112°C |
| Boiling Point | 101°C |
| Flash Point | 25°C |
| Water Solubility | Slightly soluble |
| Solubility | Soluble in ethanol, ether, chloroform |
| Vapor Pressure | 10 mmHg at 25°C |
| Vapor Density | 4.6 |
| pKa | 16.5 |
| pH | Neutral |
1-Bromobutane Safety and Hazards
1-Bromobutane is a hazardous chemical that should be handled with caution. It is toxic if ingested or inhaled and can cause irritation to the skin and eyes upon contact. The chemical is also flammable and can pose a fire hazard if exposed to heat, sparks or flames. It is important to wear proper protective equipment such as gloves, goggles and a lab coat when handling 1-Bromobutane. The chemical should be stored in a cool, dry, well-ventilated area and kept away from sources of ignition. In case of accidental exposure, immediately flush the affected area with water and seek medical attention.
| Hazard Symbols | T, F |
| Safety Description | Keep away from heat, sparks, and flames. Wear protective gloves/eye protection/face protection. IF INHALED: Remove victim to fresh air and keep at rest in a position comfortable for breathing. IF SWALLOWED: Call a POISON CENTER or doctor/physician if you feel unwell. Rinse mouth. Store in a well-ventilated place. Keep cool. Dispose of contents/container in accordance with local/regional/national/international regulations. |
| UN Ids | UN1126 |
| HS Code | 290339 |
| Hazard Class | 3 |
| Packing Group | II |
| Toxicity | Toxic if ingested or inhaled. Can cause skin and eye irritation. |
1-Bromobutane Synthesis Methods
C4H9Br can be synthesized through the reaction of 1-butanol and hydrobromic acid (HBr) in the presence of sulfuric acid (H2SO4) as a catalyst. This is known as the acid-catalyzed halogenation reaction. The reaction proceeds as follows:
- HBr is added to 1-butanol in the presence of sulfuric acid.
- The HBr protonates the hydroxyl group of the 1-butanol, creating a good leaving group (water).
- The leaving group (water) is replaced by the bromide ion (Br-) from the HBr, forming C4H9Br.
- The reaction mixture is then heated to distill off the C4H9Br.
Another method of synthesizing C4H9Br involves reacting butene with hydrogen bromide in the presence of a peroxide initiator such as benzoyl peroxide or t-butyl peroxide. This is known as the free-radical halogenation reaction. The reaction proceeds as follows:
- Butene is added to a mixture of hydrogen bromide and a peroxide initiator.
- The peroxide initiator undergoes homolytic cleavage, producing two reactive radicals.
- The radicals attack the double bond of the butene, forming a bromide radical and a carbon-centered radical.
- The bromide radical then reacts with the carbon-centered radical, forming C4H9Br.
Both of these methods are widely used for the synthesis of C4H9Br and can be optimized to produce high yields of the product. However, it is important to follow proper safety precautions when working with hazardous chemicals such as HBr and peroxides.
1-Bromobutane Uses
C4H9Br is a versatile chemical that is used in various industrial and laboratory applications.
- Organic chemists use C4H9Br as a starting material to synthesize other organic compounds, especially for producing pharmaceuticals and agrochemicals.
- Chemical reactions require C4H9Br as a solvent, and it acts as a reagent in organic synthesis.
- Manufacturers incorporate C4H9Br into flavors, fragrances, and other aroma compounds. Additionally, it is a component in surfactant production, widely used in cleaning agents such as detergents and soaps.
- C4H9Br functions as an octane booster in gasoline additives, and it is utilized in refrigerants and polymer production.
- Analytical techniques such as gas chromatography require C4H9Br as a standard reference material in the laboratory. Organic chemistry teaching and research labs use it as a starting material for various experiments.
Overall, the versatile properties of C4H9Br make it an important chemical in the fields of chemistry, pharmaceuticals, and industry, with a wide range of applications in organic synthesis, manufacturing, and research.
Questions:
Your task is to convert 2-bromobutane to 1-butene in the highest yield. Which reagents would you use?
To convert 2-bromobutane to 1-butene in the highest yield, I would use a strong base such as sodium ethoxide (NaOEt) in ethanol as the reagent. The reaction would proceed as an elimination reaction known as a dehydrohalogenation reaction.
The reaction would proceed as follows:
- 2-bromobutane is added to a solution of sodium ethoxide in ethanol.
- The strong base abstracts a proton from the beta-carbon adjacent to the bromine, forming an alkoxide ion intermediate.
- The alkoxide ion intermediate undergoes elimination of the leaving group (bromine), resulting in the formation of the alkene (1-butene) and sodium bromide.
- The reaction mixture is then distilled to remove the 1-butene product.
By using a strong base such as NaOEt, the reaction can be driven towards the formation of 1-butene, and by using ethanol as the solvent, the reaction can be carried out in a relatively safe and cost-effective manner. Additionally, the use of a strong base and ethanol as the solvent can lead to high yields of 1-butene.
Why start with 1-bromobutane for your nai in the acetone test?
Starting with C4H9Br for the NAI in the acetone test is a useful way to determine whether a given organic compound contains a halogen atom or not. The test involves the addition of sodium iodide (NaI) to the organic compound dissolved in acetone, followed by the addition of a small amount of chlorine or iodine.
The reaction proceeds by the following mechanism:
- NaI is added to the organic compound dissolved in acetone, leading to the formation of the sodium halide salt and the corresponding organic halide.
- The addition of a small amount of chlorine or iodine leads to the formation of a small amount of halogen gas, which reacts with the sodium halide salt to form the corresponding halogen gas.
- The halogen gas then reacts with the organic halide to form a colored precipitate, indicating the presence of the halogen in the original organic compound.
C4H9Br is a commonly used compound for this test because it is a simple and easily accessible organic compound that contains a halogen atom (bromine). It also reacts readily with sodium iodide and halogen gas to form a colored precipitate, making it a useful test compound for detecting the presence of a halogen in other organic compounds.