Anhydrous potassium phosphate promoted the aza-Markovnikov addition of a variety of N-heterocycles to vinyl esters in DMF at room temperature in moderate to excellent yields.
Basic Ionic Liquid as Catalysis and Reaction Medium: A Novel and Green Protocol for the Markovnikov Addition of <i>N</i>-Heterocycles to Vinyl Esters, Using a Task-Specific Ionic Liquid, [bmIm]OH
作者:Jian-Ming Xu、Bo-Kai Liu、Wei-Bo Wu、Chao Qian、Qi Wu、Xian-Fu Lin
DOI:10.1021/jo0600914
日期:2006.5.1
A basicionicliquid, 1-methyl-3-butylimidazolium hydroxide ([bmIm]OH), has been introduced as a catalyst and reactionmedium for the Markovnikov addition of N-heterocycles to vinyl esters under mild conditions. The evidence for the role of this basicionicliquid [bmIm]OH in promoting the Markovnikov addition has been given. On the basis of the evidence, a mechanism was postulated.
A novel and highly efficient protocol for Markovnikov’s addition using ionic liquid as catalytic green solvent
作者:Jian-Ming Xu、Wei-Bo Wu、Chao Qian、Bo-Kai Liu、Xian-Fu Lin
DOI:10.1016/j.tetlet.2006.01.001
日期:2006.3
A novel and highly efficient protocol for Markovnikov’s addition using ionic liquid as a catalytic green solvent is described. The strategy is especially useful in the synthesis of N-heterocycle derivatives with biological activity. This reaction widens largely the applicability of ionic liquid in organic synthesis.
A simple and efficient methodology for Markovnikov addition of azoles with vinyl acetate catalyzed by potassiumtert-butoxide is described. N-heterocyclic compounds are synthesized from simple and commercially available starting materials under mild conditions in high yields.
The present invention provides the use of a hollow particulate glass as a support for an active agent, characterised in that said hollow particulate glass is produced by pyrolysis of glass-coated polymer particles which are produced by copolymerising an unsaturated heterocyclic monomer and squaric acid,
wherein said polymer has the structure:
where each R, which may be the same or different, is hydrogen or optionally substituted alkyl; the ring nitrogen atom of the heterocyclic ring is unsubstituted or alkyl (especially methyl) substituted; X is a bond or a bridging group (preferably a bond); y is zero or a positive integer (preferably zero); and z is a positive integer the value whereof determines the molecular weight of the polymer.