Catalyst For Acylation Reactions Research Articles

ChemInform Abstract: Indium Triflate: An Efficient Catalyst for Acylation Reactions.

Indium triflate is shown to be an extremely efficient catalyst for the acylation of alcohols and amines.

ChemInform Abstract: An Efficient Method for Diacetylation of Aldehydes.

Cu(OTf) 2 was found to be an efficient catalyst for acylation reaction of aldehydes with acetic anhydride in CH 2 Cl 2 .

Air-stable titanocene bis(perfluorooctanesulfonate) as a new catalyst for acylation of alcohols, phenols, thiols, and amines under solvent-free condition

Air-stable titanocene bis(perfluorooctanesulfonate) [Cp 2Ti(OSO 2C 8F 17) 2] that shows high Lewis acidity was prepared from Cp 2TiCl 2 and AgOSO 2C 8F 17. The compound was characterized by different techniques, and examined as a catalyst for acylation reactions. It was found that using equimolar acetic anhydride as acetylating agent and under solvent-free condition, Cp 2Ti(OSO 2C 8F 17) 2 exhibits high activity and selectivity in the acetylation of various alcohols, phenols, thiols, and amines. Also, good catalytic efficiency is observed in the acylation of 2-phenylethanol across various acylating reagents. The catalyst can be reused without loss of activity in a test of ten cycles. The Cp 2Ti(OSO 2C 8F 17) 2 catalyst affords a simple, efficient and general method for the acylation of alcohols, phenols, thiols, and amines.

Zirconocene bis(perfluorooctanesulfonate)s-catalyzed acylation of alcohols, phenols, thiols, and amines under solvent-free conditions

Air-stable zirconocene bis(perfluorooctanesulfonate)s [Cp2Zr(OPf)2, OPf = OSO2C8F17] showing high Lewis acidity and high thermal stability was prepared by reacting Cp2ZrCl2 with AgOPf, and examined as a catalyst for acylation reactions. It was found that in the acetylation of various alcohols, phenols, thiols, and amines by equimolar of acetic anhydride, Cp2Zr(OPf)2 exhibits high activity and selectivity to desired products under mild and solvent-free conditions. In the acylation of 2-phenylethanol across various acylating reagents, it also shows good catalytic efficiency. In a test of ten cycles, Cp2Zr(OPf)2 shows little loss of activity. The results afford a general and efficient method for the acylation of alcohols, phenols, thiols, and amines using zirconium bis(perfluorooctanesulfonate) as catalyst.

Amberlyst-15-Catalyzed Efficient Synthesis of 1,1-Diacetates from Aldehydes#

Amberlyst-15 was found to be an efficient catalyst for acylation reaction of aldehydes with acetic anhydride at room temperature in dichloromethane. #IICT Communication No. 01/09/04.

Bismuth(III) Trifluoromethanesulfonate: An Efficient Catalyst for the Sulfonylation of Arenes

Sulfonylation reactions are one of the most important groups of aromatic electrophilic substitutions.1 The sulfonyl group is a widely used synthon for synthetic organic chemists,2 and sulfones have many industrial applications.3 In Friedel-Crafts (FC) acylation and sulfonylation, a consequence of the complexation of the Lewis acid with the reaction product implies that a stoichiometric amount of the activator is often required. However, some metal halides such as iron(III) chloride,1 Bronsted acids, for example polyphosphoric acid4 or triflic acid,5 and zeolites6,7 have been reported to catalyze the sulfonylation of arenes. In recent years, rare earth trifluoromethanesulfonates (triflates) have been reported for the catalysis of the FC acylation8 but not for the catalysis of the FC sulfonylation. Also, our laboratory reported that bismuth(III) chloride (1a) and particularly bismuth(III) triflate (1b) were catalysts for acylation reactions,9 especially for FC acylation.10 In a stoichiometric process from arylsulfonyl bromides, silver triflate gives trifluoromethanesulfonic arenesulfonic anhydrides (ArSO2OTf), which are strong sulfonylating reagents.11 We present here a study of the catalytic activity of 1a and 1b for the sulfonylation reaction of arenes (eq 1), for which 1b proved to be a metal triflate capable of realizing an outstanding catalytic process.