Stilbenes Preparation and Analysis

This monograph is intended for scientists working on chemistry, physics, and biology of stilbenes and related areas such as optical materials and devices production, molecular biophysics, plant biochemistry, biomedicine, and pharmacology. The book can also be used as a subsidiary manual for instructors and graduate and undergraduate students of university physics, biochemistry, and chemistry departments. 

The name for stilbene (1,2-diphenylethylene) was derived from the Greek word stilbos, which means shining. There are two isomeric forms of 1,2-diphenylethylene ( )-stilbene (trans-stilbene), which is not sterically hindered, and (Z)-stilbene (cis-stilbene), which is sterically hindered and therefore less stable. 

Stilbene derivatives are synthesized relatively easily, are usually thermally and chemically stable, and possess absorption and fluorescence properties that are 

Stilbenes. Applications in Chemistry, Life Sciences and Materials Science. Gertz Likhtenshtein Copyright 2010 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 97S-3-527-32388-3 

Hydroxylated derivatives of stilbene (stilbenoids) are secondary products of heartwood formation in trees that can act as phytoalexins (antibiotics produced by plants). 

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The mesoporous character of MCM-41 overcomes the size limitations imposed by the use of zeolites and it is possible to prepare the complex by refluxing the chiral ligand in the presence of Mn +-exchanged Al-MCM-41 [34-36]. However, this method only gives 10% of Mn in the form of the complex, as shown by elemental analysis, and good results are only possible due to the very low catalytic activity of the uncomplexed Mn sites. The immobihzed catalyst was used in the epoxidation of (Z)-stilbene with iodosylbenzene and this led to a mixture of cis (meso) and trans (chiral) epoxides. Enantioselectivity in the trans epoxides was up to 70%, which is close to the value obtained in solution (78% ee). However, this value was much lower when (E)-stilbene was used (25% ee). As occurred with other immobilized catalysts, reuse of the catalyst led to a significant loss in activity and, to a greater extent, in enantioselectivity. 

Several synthesis on the basis of stilbenes as starting materials were reported. The paper [113] presented experimental data regarding some azo dyes synthesized by coupling of the diazonium salt of 4,4 -diarnino-stUbene-2,2 -disulfonic add with different acetoacetarylides. Reaction products were purified and characterized by means of elemental analysis by UV-VIS, IR, H-NMR, and C-NMR spectroscopy. A series of stilbene and fluorene compounds were prepared [114]. Compounds of... 

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