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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.
Le Bel-van't Hoff rule states that for a structure with n asymmetric carbon atoms, there is a maximum of 2 n different stereoisomers possible. As an example, D-glucose is an aldohexose and has the formula C 6 H 12 O 6. Four of its six carbon atoms are stereogenic, which means D-glucose is one of 2 4 =16 possible stereoisomers. [20] [21]
Stilbene may refer to one of the two stereoisomers of 1,2-diphenylethene: -Stilbene (trans isomer) -Stilbene (cis isomer) See also.
In E-Z isomerization, the thermal equilibrium lies well towards the trans-form because of its lower energy (~15 kJ mol −1 in stilbene). [3] 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 ...
Spiropyran and Merocyanine undergo ring opening/closing mechanisms upon photo irradiation. Diarylethene and donor-acceptor Stenhouse adducts exhibit changes in color upon photoisomerization. Stilbene is a model photoswitch for studying photochemistry. A photochromic compound can change its configuration or structure upon irradiation with light.
In organic chemistry, syn-and anti-addition are different ways in which substituent molecules can be added to an alkene (R 2 C=CR 2) or alkyne (RC≡CR).The concepts of syn and anti addition are used to characterize the different reactions of organic chemistry by reflecting the stereochemistry of the products in a reaction.
Since the factors underlying these desiderata are at odds, tuning of the catalyst properties has proven difficult. Shown below are several of the most successful catalysts along with the yields and enantiomeric excess for their use in synthesis of (E)-stilbene oxide. [5] [2] chiral catalysts for the Johnson–Corey–Chaykovsky reaction
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.