713510-75-9Relevant academic research and scientific papers
Acetonyltriphenylphosphonium bromide (ATPB): A versatile reagent for the acylation of alcohols, phenols, thiols and amines and for 1,1-diacylation of aldehydes under solvent-free conditions
Khan, Abu T.,Choudhury, Lokman H.,Ghosh, Subrata
, p. 2782 - 2787 (2007/10/03)
A wide variety of alcohols, phenols, amines and thiols may easily be converted into the corresponding acetate derivatives by treatment with acetic anhydride (1.5-2.0 equivalents) in the presence of acetonyltriphenylphosphonium bromide (ATPB; 5 mol %) in good yields at room temperature. With the same precatalyst, both aliphatic and aromatic aldehydes can also be transformed into the corresponding gemdiacetates under reflux conditions.
Reinvestigation of the mechanism of gem-diacylation: Chemoselective conversion of aldehydes to various gem-diacylates and their cleavage under acidic and basic conditions
Kavala, Veerababurao,Patel, Bhisma K.
, p. 441 - 451 (2007/10/03)
The mechanism of gem-diacylate formation has been studied extensively using tetrabutylammonium tribromide (TBATB) as the catalyst. The reaction proceeds by a nucleophilic attack of an anhydride on an aldehydic carbonyl group, nucleophilic attack of the hemiacylate intermediate on a second molecule of the anhydride, followed by an intermolecular attack of a second acetate group to regenerate the anhydride. gem-Diacylates of various aliphatic and aromatic aldehydes were obtained directly from the reaction of a variety of aliphatic and aromatic acid anhydrides in the presence of a catalytic quantity of tetrabutylammonium tribromide (TBATB) under solvent-free conditions. A significant electronic effect was observed during its formation as well as deprotection to the corresponding aldehyde. Chemoselective gem-diacylation of the aromatic aldehyde containing an electron-donating group has been achieved in the presence of an aldehyde containing an electron-withdrawing group. Deprotection of the gem-diacylate to the parent carbonyl compound can be accomplished in methanol in presence of the same catalyst. Here again, chemoselective deprotection of the gem-diacylate of a substrate containing an electron-donating group has been achieved in the presence of a substrate containing an electron-withdrawing group. Both the acid and base stability order of the various gem-diacylates examined follow a similar order. The stability order determined from the present study is: gem-dibenzoate > gem-dipivalate > gem-diisobutyrate > gem-diacetate > gem-dipropionate. All the gem-diacylals are more stable under basic conditions than acidic condition. No correlation was found between the stability order and the pKa's of the corresponding acids; rather, the stability order is directly related to the steric crowding around the carbonyl carbon. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Copper(II) tetrafluoroborate-catalyzed formation of aldehyde-1,1-diacetates
Chakraborti, Asit K.,Thilagavathi, Ramasamy,Kumar, Raj
, p. 831 - 833 (2007/10/03)
Aldehyde 1,1-diacetates are farmed in excellent yields from aldehydes and acetic anhydride under solvent-free conditions at room temperature in short times in the presence of a catalytic amount of copper(II) tetrafluoroborate hydrate.
Lithium trifluoromethanesulfonate (LiOTf) as a recyclable catalyst for highly efficient acetylation of alcohols and diacetylation of aldehydes under mild and neutral reaction conditions
Karimi, Babak,Maleki, Jafar
, p. 4951 - 4954 (2007/10/03)
A variety of alcohols and aldehydes were reacted with acetic anhydride at room temperature in the presence of a catalytic amount of lithium triflate (LiOTf) to produce the corresponding esters and 1,1-diacetates, respectively, in good to excellent yields under essentially neutral reaction conditions. Sensitive functional groups such as PhCO2-, OMe, and OTBDMS ethers survived intact under the described reaction conditions.
