(''Z'')-Stilbene is a

diarylethene Diarylethene is the general name of a class of chemical compounds that have aromatic functional groups bonded to each end of a carbon–carbon double bond. The simplest example is stilbene, which has two geometric isomers, E and Z. Under the influ ...

, that is, a

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...

consisting of a cis

ethene Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon-carbon double bonds). Ethylene i ...

double bond substituted with a

phenyl In organic chemistry, the phenyl group, or phenyl ring, is a cyclic group of atoms with the formula C6 H5, and is often represented by the symbol Ph. Phenyl group is closely related to benzene and can be viewed as a benzene ring, minus a hydrogen ...

group on both carbon atoms of the double bond. The name stilbene was derived from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

word , which means shining.

Isomers

Stilbene exists as two possible isomers known as (''E'')-stilbene and (''Z'')-stilbene. (''Z'')-Stilbene is

sterically hindered Steric effects arise from the spatial arrangement of atoms. When atoms come close together there is a rise in the energy of the molecule. Steric effects are nonbonding interactions that influence the shape ( conformation) and reactivity of ions ...

and less stable because the steric interactions force the aromatic rings 43° out-of-plane and prevent

conjugation Conjugation or conjugate may refer to: Linguistics *Grammatical conjugation, the modification of a verb from its basic form * Emotive conjugation or Russell's conjugation, the use of loaded language Mathematics *Complex conjugation, the change ...

. (''Z'')-Stilbene has a melting point of , while (''E'')-stilbene melts around , illustrating that the two compounds are quite different.

Uses

* Stilbene is used in manufacture of

dye A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution and ...

s and optical brighteners, and also as a

phosphor A phosphor is a substance that exhibits the phenomenon of luminescence; it emits light when exposed to some type of radiant energy. The term is used both for fluorescent or phosphorescent substances which glow on exposure to ultraviolet or v ...

and a

scintillator A scintillator is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate (i.e. re-emit the absorbe ...

. * Stilbene is one of the

gain medium The active laser medium (also called gain medium or lasing medium) is the source of optical gain within a laser. The gain results from the stimulated emission of photons through electronic or molecular transitions to a lower energy state from a h ...

s used in

dye laser A dye laser is a laser that uses an organic dye as the lasing medium, usually as a liquid solution. Compared to gases and most solid state lasing media, a dye can usually be used for a much wider range of wavelengths, often spanning 50 to 100 ...

Properties

* Stilbene will typically have the chemistry of a

, a conjugated

alkene In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond. Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic ...

. * Stilbene can undergo

photoisomerization In chemistry, photoisomerization is a form of isomerization induced by photoexcitation. Both reversible and irreversible photoisomerizations are known for photoswitchable compounds. The term "photoisomerization" usually, however, refers to a re ...

under the influence of UV light. * Stilbene can undergo

stilbene photocyclization In organic chemistry, the Mallory reaction is a photochemical-cyclization– elimination reaction of diaryl-ethylene structures to form phenanthrenes and other polycyclic form polycyclic aromatic hydrocarbons and heteroaromatics.Mallory, F. B.; Mal ...

, an intramolecular reaction. * (Z)-Stilbene can undergo electrocyclic reactions.

Natural occurrence

Many stilbene derivatives (

stilbenoid Stilbenoids are hydroxylated derivatives of stilbene. They have a C6–C2–C6 structure. In biochemical terms, they belong to the family of phenylpropanoids and share most of their biosynthesis pathway with chalcones. Most stilbenoids are prod ...

s) are present naturally in plants. An example is

resveratrol Resveratrol (3,5,4′-trihydroxy-''trans''-stilbene) is a stilbenoid, a type of natural phenol, and a phytoalexin produced by several plants in response to injury or when the plant is under attack by pathogens, such as bacteria or fungi. Sourc ...

and its cousin,

pterostilbene Pterostilbene () (trans-3,5-dimethoxy-4-hydroxystilbene) is a stilbenoid chemically related to resveratrol. In plants, it serves a defensive phytoalexin role. Natural occurrence Pterostilbene is found in almonds, various ''Vaccinium'' berries ( ...

References

{{DEFAULTSORT:Stilbene, (Z)- Luminescence Fluorescent dyes Phosphors and scintillators Laser gain media Stilbenoids Phenyl compounds