Current Organic Chemistry - Volume 15, Issue 23, 2011

Its outstanding ability to generate singlet oxygen or reactive oxygen species upon irradiation with light makes hypericin one of the most powerful photosensitizers to be found in Nature. The most important fields of application of hypericin seem presently to be its use as a photosensitizing antiviral agent to destroy virus particles in blood preparations, to sensitize the destruction of superficial tumors, and its use as a diagnos Read More

Combined reactions through organoboron intermediates belong to the class of sequential reactions whereby the advantages are clear in terms of efficiency and selectivity. The goal to prepare target molecules from simple substrates requires strategic steps and very selective formation of new bonds. The addition of boryl units to unsaturated substrates can be performed chemo-, regio- and stereoselectively, therefore the organ Read More

The methods to prepare Nafion materials with significantly improved specific activities, their characterization and applications as useful and efficient catalysts are summarized. The sol-gel technique used most widely, covalent anchoring of the sulfonic acid group to the surface via a perfluoroalkane tether via post-synthesis modification, impregnation of high-porosity spinodal silica and mesoporous silica materials, an Read More

This review highlights the application of sulfated, molybdated and tungstated zirconia solid acid catalysts, and their modified forms for variety of organic synthesis and transformation reactions in the liquid phase. Most of these catalysts offer significant improvements in various organic reactions with regard to the yield of products, simplicity in the operation, reusability of the catalysts and green features by avoiding toxi Read More

Triphenylphosphine (TPP), dialkyl acetylenedicarboxylates (DAAD), and acids such as phenols, imides, amides, enols, oximes and alcohols react with each other via a multicomponent reaction to produce stabilized phosphorus ylides. The reactions take place easily, through formation of intermediate formed by the Michael addition of the triphenylphosphine to dialkyl acetylenedicarboxylates and concomitant protonation o Read More