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E)-Stilbene itself is of little value, but it is a precursor to other derivatives used as dyes, optical brighteners, phosphors, and scintillators. [25] Stilbene is one of the gain mediums used in dye lasers. [26] 4,4 ′-diamino-2,2 ′-stilbenedisulfonic acid is a popular optical brightener used in some laundry detergents.
The activation energy for thermal E-Z isomerization is 150–190 kJ mol −1 for stilbene, meaning that temperatures above 200°C are required to isomerize stilbene at a reasonable rate, but most derivatives have lower energy barriers (e.g. 65 kJ mol −1 for 4-aminostilbene). The activation energy of the electrocyclization is 73 kJ mol −1 ...
Suitably substituted stilbenes may undergo irreversible, rearomatizing elimination or [1,n]-shift processes in the absence of an oxidant. Aryl enynes, [4] heteroatomic stilbene derivatives (e.g. amides [5]), and substrates containing a single heteroatom in place of the stilbene double bond [6] also undergo the reaction.
It is a white, water-soluble solid. Structurally, it is a derivative of trans-stilbene, containing amino and sulfonic acid functional groups on each of the two phenyl rings. The compound is a popular optical brightener for use in laundry detergents. It is produced by reduction of 4,4′-dinitro-2,2′-stilbenedisulfonic acid with iron powder. [1]
The 1,3-dipolar cycloaddition is a chemical reaction between a 1,3-dipole and a dipolarophile to form a five-membered ring. The earliest 1,3-dipolar cycloadditions were described in the late 19th century to the early 20th century, following the discovery of 1,3-dipoles.
Resveratrol is a biologically important stilbenoid.. Stilbenoids are hydroxylated derivatives of stilbene.They have a C 6 –C 2 –C 6 structure. In biochemical terms, they belong to the family of phenylpropanoids and share most of their biosynthesis pathway with chalcones.
(Z)-Stilbene is sterically hindered and less stable because the steric interactions force the aromatic rings 43° out-of-plane and prevent conjugation. [2] (Z)-Stilbene has a melting point of 5–6 °C (41–43 °F), while (E)-stilbene melts around 125 °C (257 °F), illustrating that the two compounds are quite different.
Stilbene may refer to one of the two stereoisomers of 1,2-diphenylethene: -Stilbene (trans isomer) -Stilbene (cis isomer) See also. Stilbenoids, a class of ...