2,5-Norbornadiene

Chemical properties

2,5-Norbornadiene, also known as dicycloheptadiene, is a clear colorless to slightly yellow liquid that is soluble in petroleum ether and insoluble in water. Commercially available goods usually contain 500 ppm of 2,6-di-tert-butyl-p-methylphenol (BHT) as a stabilizer. Analyzing the structural characteristics of NBD, it can be found that it has good reaction properties and can synthesize a variety of organic compounds through addition or substitution reactions at the double bond.

The Uses of 2,5-Norbornadiene

2,5-Norbornadiene has an anti-ethylene effect on plants and inhibits polyphenol oxidase, peroxidase and phenylalanine ammonia lyase activities.

The Uses of 2,5-Norbornadiene

2,5-Norbornadiene is used as an intermediate in prostaglandin synthesis and shows anti-ethylene effect on plants. It acts as a starting material for the synthesis of diamantane and as an acetylene transfer agent for instance, in reaction with 3,6-di-2-pyridyl-1,2,4,5-tetrazine. It is also a useful dienophile in Diels-Alder reactions.

What are the applications of Application

Bicyclo[2.2.1]hepta-2,5-diene is an intermediate in prostaglandin synthesis

Preparation

2,5-Norbornadiene is of interest as a metal-binding ligand, whose complexes are useful for homogeneous catalysis. Norbornadiene can be formed by a Diels-Alder reaction between cyclopentadiene and acetylene.

General Description

2,5-norbornadiene, stabilized appears as a colorless liquid. Insoluble in water and less dense than water. Contact may irritate skin, eyes and mucous membranes. May be toxic by ingestion, inhalation and skin absorption. When heated will polymerize and at decomposition emits acrid smoke and irritating fumes.

Air & Water Reactions

Highly flammable. Insoluble in water.

Reactivity Profile

2,5-NORBORNADIENE may react vigorously with strong oxidizing agents. May react exothermically with reducing agents to release hydrogen gas. In the presence of various catalysts (such as acids) or initiators, may undergo exothermic addition polymerization reactions. Violent explosions at low temperatures in ammonia synthesis gas units have been traced to the addition products of dienes and nitrogen dioxide [Bretherick, 5th Ed., 1995].

Health Hazard

Inhalation or contact with material may irritate or burn skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution.

Safety Profile

Poison by intravenous route. Moderately toxic by ingestion and intraperitoneal routes. Mildly toxic by inhalation. A flammable liquid. When heated to decomposition it emits acrid smoke and irritating fumes.

Purification Methods

Purify the diene by distillation from activated alumina [Landis & Halpern J Am Chem Soc 109 1746 1987]. [Beilstein 5 IV 879.]