When first starting out in organic chemistry, students are often tasked with synthesizing benzene. The synthesis is usually done in a lab setting and the following reagents are used:
Ethanol (reaction 1)
Acetone (2)
Sodium hydroxide (3)
Potassium permanganate (4)
Sulfuric acid (5)
Trifluoroacetic acid (TFAA)
Nitrosyl chloride (NCl)
Phosphorus pentachloride (PCl)
Toluene in ethanol, followed by a solution of sodium amide in water. Finally, the product is filtered and dried to get pure benzene crystalized from ether. This synthesis requires many steps with multiple materials and therefore it can be expensive for students. Moreover, not all reagents are easy to find or their availability varies depending on where you live.”
Benzene Reactivity: What Makes Benzene so Unique? – “The reactivity difference between hydrogenation reactions depends on how easily a molecule will undergo electrophilic or nucleophilic attack. Hydrogenation is one of the few chemical reactions in which atoms can be transferred between molecules through covalent bonds.”
hydrogenation (electrophilic or nucleophlic)
benzene reactivity
How easily a molecule will undergo electrophilic or nucleophlic attack?
What makes benzene so unique? – “The reactivity difference between hydrogenation reactions depends on how easily a molecule will undergo electrophilic or nucleophulic attack”
The Benzene Molecule and its Structure, Properties, Uses and Hazards to Humans – “Benzene has six carbon atoms in two hexagons that are connected by single bonds in a ring. Benzene is classified as an aromatic compound because it has a benzene ring.”
“Benzene reacts with electrophiles to form cationic intermediates, and nucleophles react by causing benzenes to lose electrons that are then transferred as proton or electron equivalents”
Reagent: hydrogenation (electrophilic) Conditions: high pressure; palladium on charcoal catalyst; reaction temperature of 150 degrees Celsius for 30 minutes at atmospheric pressures.
How easily a molecule will undergo electrophilic or nucleophlic attack? – the most reactive atom in the molecule determines which type of reaction happens first. If there’s more than one available position for an attacking reagent,
high boiling point
low vapor pressure
good thermal stability
which make them ideal for use in fuel cells and electrolysis systems. This property also causes a difference in reactivity between hydrogenation reactions, which depend on how easily a molecular can be subjected to an electrophilic addition”.”
the reactivity of Benzene is much higher than that of Alkenes because it allows reaction with electron donating groups such as alcohols or phenols.. In contrast, alkenes tend to form less stable covalent bonds during these kinds of substitutions. These sorts of differences are accounted for when considering the chemical synthesis needed to produce many plastics made of polymers such as Polyethylene and Polypropylene.
Benzene reacts with acids to form the corresponding benzyl compounds in addition reactions. For example, phenol is reacted aggressively with nitric acid HNOONOto produce a white solid of CphenyllnitrateHN0:
This reaction product has been implicated in significant environmental pollution when used for cleaning oil spills and on dirty cars/buildings. In contrast, benzoic acid undergoes oxidation by air oxygen to give an unstable mixture that becomes explosive on contact with organic materials or other sources of ignition, e.g., gasoline vapors from motors.:
benzene can be oxidized easily under certain conditions but it does not react much with acids.
benzene will react with nitric acid to produce phenylnitrate in addition reactions, but benzoic acid reacts by oxidation of air oxygen and produces an unstable mixture that becomes explosive on contact with organic materials or other sources of ignition like gasoline vapors from motors.
polymers such as Polyethylene and Polypropylene are formed in the reaction between benzene and sulfuric acid which can be found in car batteries.:
In contrast, polystyrene is a solid material created through polymerization involving chloroform (CCl) under conditions where heat is applied:
The first step involves condensing terephthalaldehyde molecules into dimers; this product then undergoes dehydrochlorination in a step that is catalyzed by aluminum chloride, to produce the desired polymer.
enzene will react with nitric acid
benzoic acid reacts by oxidation of air oxygen and produces an unstable mixture that becomes explosive on contact with organic materials or other sources of ignition like gasoline vapors from motors.
When benzene is reacted to form benzonitrile, it undergoes a substitution reaction in which the hydrogen attached to one carbon atom (the alpha-carbon) is replaced by a cyanide group (-C≡N). The resultant compound has five atoms in its nucleus: four carbons, including the new nitrogen atom; and one oxygen atom.
In contrast, polystyrene is a solid material created through polymerization involving chloroform (CCl) under conditions where heat is applied:
