Surfactant-Type Brønsted Acid Catalyzed Dehydrative Nucleophilic Substitutions of Alcohols in Water
作者:Seiji Shirakawa、Shū Kobayashi
DOI:10.1021/ol062813j
日期:2007.1.1
A protocol for the dehydrative nucleophilicsubstitution of benzyl alcohols with a variety of carbon- and heteroatom-centered nucleophiles using dodecylbenzenesulfonic acid (DBSA) as a surfactant-type Bronsted acid catalyst in water has been developed. The reaction system can be applied to the stereoselective C-glycosylation of 1-hydroxy sugars in water. [reaction: see text].
Tritylium assisted iodine catalysis for the synthesis of unsymmetrical triarylmethanes
作者:Thibaut Courant、Marine Lombard、Dina V. Boyarskaya、Luc Neuville、Géraldine Masson
DOI:10.1039/d0ob01502d
日期:——
The combined Lewis acid catalytic system, generated from molecular iodine and tritylium tetrafluoroborate effectively catalyzed the Friedel–Crafts (FC) arylation of diarylmethyl sulfides providing an efficient access to various unsymmetrical triarylmethanes. The addition of tritylium and iodine created a more active catalytic system to promote the cleavage of sulfidic C–S bonds.
Brønsted Acid-Catalyzed Nucleophilic Substitution of Alcohols
作者:Roberto Sanz、Alberto Martínez、Delia Miguel、Julia M. Álvarez-Gutiérrez、Félix Rodríguez
DOI:10.1002/adsc.200606183
日期:2006.9
Brønsted acids such as p-toluenesulfonic acid monohydrate (PTS) or polymer-bound p-toluenesulfonic acid efficiently catalyze the direct nucleophilic substitution of the hydroxygroup of allylic and benzylic alcohols with a large variety of carbon- and heteroatom-centered nucleophiles. Reaction conditions are mild, the process is conducted under an atmosphere of air without the need for dried solvents
In high-temperature water a series of benzyl and allylic alcohols reacted with 1,3-dicarbonyl compounds and activated aromatic compounds to give the alkylated products without added catalysts.
Simple and efficient procedure for alkylation of aromatics from alcohols in the presence of NaHSO4/SiO2 was developed. Various triaryl methanes were obtained in good yields in short reaction time. For instance the reaction of mesitylene with benzhydrol in the presence of NaHSO4/SiO2 gave the corresponding triaryl methane in a quantitative yield. NaHSO4/SiO2 was regenerated by simple treatment and could