413601-57-7Relevant academic research and scientific papers
A facile and efficient conversion of aldehydes into 1,1-diacetates (acylals) using iron(III) fluoride as a novel catalyst
Kamble,Tayade,Davane,Kadam
, p. 590 - 594 (2008/03/11)
Aldehydes are smoothly converted into the corresponding 1,1-diacetates (acylals) in high yields in the presence of a catalytic amount (0.1 mol-%) of iron(III) fluoride at room temperature. The noteworthy features of the present system are shorter reaction times, chemoselective protection of aldehydes, and solvent-free conditions. The procedure is especially useful for large-scale syntheses as the catalyst is highly effective from the view of activity, selectivity, reusability, and economy in the preparation of 1,1-diacetates (acylals). CSIRO 2007.
An efficient method for the synthesis of acylals from aldehydes using silica-supported perchloric acid (HClO4-SiO2)
Kamble, Vinod T.,Jamode, Vasant S.,Joshi, Neeta S.,Biradar, Ankush V.,Deshmukh, Rameshchandra Y.
, p. 5573 - 5576 (2007/10/03)
The synthesis of acylals from structurally diverse aldehydes has been performed in excellent yields under solvent-free conditions using HClO4-SiO2 as a mild, convenient, reusable, and heterogeneous catalyst. The procedure is operationally simple, environmentally benign and has the advantage of enhanced atom utilization. Furthermore, the catalyst can be recovered simply and reused efficiently a number of times without appreciable loss of activity.
A remarkable HBF4-SiO2-catalyzed synthesis of acylals from aldehydes under solvent-free conditions
Kamble, Vinod T.,Bandgar, Babasaheb P.,Joshi, Neeta S.,Jamode, Vasant S.
, p. 2719 - 2722 (2008/02/11)
HBF4-SiO2 has been found to be an outstanding catalyst for the protection of carbonyl compounds as acylals under entirely solvent-free conditions. Some of the major advantages of this procedure are high yields, ease of operation, high chemoselectivity, high atom efficiency, and compatibility with other protecting groups. Georg Thieme Verlag Stuttgart.
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.
Bismuth compounds in organic synthesis. Bismuth nitrate catalyzed chemoselective synthesis of acylals from aromatic aldehydes
Aggen, David H.,Arnold, Joshua N.,Hayes, Patrick D.,Smoter, Nathaniel J.,Mohan, Ram S.
, p. 3675 - 3679 (2007/10/03)
Aromatic aldehydes are smoothly converted into the corresponding acylals in good yields in the presence of 3-10mol% Bi(NO3) 3·5H2O. Ketones are not affected under the reaction conditions. The relatively non-toxic nature of the catalyst, its ease of handling, easy availability and low cost make this procedure especially attractive for large-scale synthesis.
Reductive esterification of aromatic aldehydes using Zn/Ac 2O/imidazole or Zn/Yb(OTf)3/(RCO)2O system
Hirao, Toshikazu,Santhitikul, Sirida,Takeuchi, Hiroki,Ogawa, Akiya,Sakurai, Hidehiro
, p. 10147 - 10152 (2007/10/03)
Benzaldehydes are reduced by metallic zinc in the presence of Ac 2O and imidazole, giving the corresponding benzyl acetates in good yields. Reductive esterification of aromatic aldehydes is also carried out via gem-diacetoxy compounds. Carbonyl compounds are readily converted to the gem-diacyloxy compounds in excellent yields on treatment with 2molar amounts of acid anhydride and 10mol% of Yb(OTf)3 in MeCN at room temperature. Thus-formed diacyloxy compounds derived from aromatic aldehydes are reduced in situ by metallic zinc to afford the corresponding esters.
Conversion of aldehydes into geminal dicarboxylates (acylals) catalyzed by lithium tetrafluoroborate
Sumida,Nishioka,Sato
, p. 1921 - 1922 (2015/11/05)
A variety of aldehydes react with acid anhydrides in the presence of a catalytic amount of lithium tetrafluoroborate to afford the corresponding geminal dicarboxylates (acylals) in good to excellent yields.
