Norbornene

• Bicyclo [2.2.1] hept -2-ene
• 8,9,10 - trinor -2- begotten

White solid with a slightly sour smell

Fixed

44-47 ° C

95-96 ° C

32 hPa ( 65 ° C)

Almost insoluble in water

Risk

11300 mg · kg -1 ( LD50, rat, oral)

Template: Infobox chemical / molecular formula search available

Norbornene, also norbornylene or Norcamphen, are common names for a bridged bicyclic hydrocarbon. At room temperature norbornene is present as white, pungent -smelling solid before. The molecule consists of a cyclohexene ring of 1,4- bridged by a methyl group. The double bond leads to a hoop stress and is responsible for the increased reactivity of the molecule.

Is norbornene, as well as many of its derivatives, prepared by the Diels- Alder reaction of cyclopentadiene with ethylene. Related bicyclic compounds are norbornadiene, which has the same carbon skeleton, but a further double bond, and norbornane, as well saturated with the same structure, but with no double bonds, and thus.

With water norbornene reacts in an acid-catalyzed reaction to norborneol. This reaction is of interest for chemists who deal with " non-classical ion" connections.

Polynorbornenes

Norbornene are important monomers for ROMP ( ring -opening metathesis polymerization, ring-opening metathesis So, see also metathesis ) is that (mostly carbene complexes of ruthenium ) polymerize under the influence of Grubbs catalysts:

Polynorbornenes are polymers, which are characterized by high glass transition temperatures and high optical clarity.

In addition to ROMP of norbornene monomers can also polymerize vinyl addition polymerizations.

Ethylidene- norbornene is a related monomer which is derived from cyclopentadiene and butadiene.

Applications

Norbornene is rarely used as ethene or other bulk chemicals. It serves as a starting material for pharmaceutical intermediates, pesticides, artificial fragrances and general organic synthesis. In combination with ethylene norbornene can be reacted to form a cyclo-olefin copolymer.