5406-58-6Relevant academic research and scientific papers
Ketalization of ketones to 1,3-dioxolanes and concurring self-aldolization catalyzed by an amorphous, hydrophilic SiO2-SO3H catalyst under microwave irradiation
Barbosa, Sandro L.,Ottone, Myrlene,De Almeida, Mainara T.,Lage, Guilherme L.C.,Almeida, Melina A.R.,Nelson, David Lee,Dos Santos, Wallans T.P.,Clososki, Giuliano C.,Lopes, Norberto P.,Klein, Stanlei I.,Zanatta, Lucas D.
, p. 1663 - 1671 (2018/06/29)
The amorphous, mesoporous SiO2-SO3H catalyst with a surface area of 115 m2 g-1 and 1.32 mmol H+ per g was very efficient for the protonation of ketones on a 10percent (m/m) basis, and the catalyst-bound intermediates can be trapped by polyalcohols to produce ketals in high yields or suffer aldol condensations within minutes under low-power microwave irradiation. The same catalyst can easily reverse the ketalization reaction. Printed in Brazil-
Silica-gel supported sulfamic acid (SA/SiO2) as an efficient and reusable catalyst for conversion of ketones into oxathioacetals and dithioacetals
Aoyama, Tadashi,Suzuki, Toshihiko,Nagaoka, Takashi,Takido, Toshio,Kodomari, Mitsuo
, p. 553 - 566 (2013/01/15)
A simple and efficient method for the conversion of carbonyl compounds to oxathioacetals and dithioacetals using SA/SiO2 as an acid catalyst has been achieved. SA/SiO2 is easily recovered from the reaction mixture and can be reused at least 15 times without loss of catalytic activity.
Indium(III) triflate catalysed transacetalisation reactions of diols and triols under solvent-free conditions
Smith, Brendan M.,Kubczyk, Tomasz M.,Graham, Andrew E.
experimental part, p. 7775 - 7781 (2012/09/21)
Acyclic acetals and ketals undergo transacetalisation in the presence of catalytic quantities of indium(III) triflate (In(OTf)3) and diols or triols under solvent-free conditions to generate the corresponding cyclic acetals and ketals in excellent yield. The methodology has been further developed to encompass a tandem acetalisation-acetal exchange protocol, which provides a facile and high yielding route to cyclic ketals from unreactive ketones under very mild reaction conditions.
Indium triflate mediated tandem acetalisation-acetal exchange reactions under solvent-free conditions
Smith, Brendan M.,Graham, Andrew E.
experimental part, p. 6281 - 6283 (2011/12/14)
Acyclic acetals and ketals undergo exchange reactions in the presence of catalytic quantities of indium(III) triflate and diols to generate the corresponding cyclic acetals and ketals in excellent yield. The protocol is rapid, employs mild conditions and can be adapted to employ solvent-free reaction conditions. We have further developed this methodology to encompass a tandem acetalisation-acetal exchange protocol which provides facile access to cyclic ketals from unreactive ketones also under very mild, solvent-free reaction conditions.
3,3,9,9-Tetramethyl-1,5,7,11-tetraoxaspiro[5.5]undecane as a reagent for protection of carbonyl compounds
Rahimizadeh, Mohammad,Bakavoli, Mehdi,Shiri, Ali,Eshghi, Hossein,Saberi, Sattar
experimental part, p. 704 - 706 (2009/09/25)
3,3,9,9-Tetramethyl-1,5,7,11-tetraoxaspiro[5.5]undecane is introduced as a new, stable and chemoselective reagent for the protection of aldehydes and ketones under mild reaction condition in high yield.
Solid supported reactions and reagents XIV [1]: Envirocat EPZG as a novel catalyst for selective acetalization of aldehydes and ketones
Bandgar, Babasaheb P.,Gaikwad, Nandkumar B.
, p. 719 - 722 (2007/10/03)
Envirocat EPZG is an efficient reusable catalyst for acetalization of aldehydes and ketones. The isolation of pure products in high yields by simple filtration and evaporation of the solvent is an important feature of this method.
Efficient Synthesis of Acetals Promoted by a Yttria-Zirconia Based Strong Lewis Acid Catalyst
Pals, Godwin C. G.,Keshavaraja,Saravanan,Kumar, Pradeep
, p. 426 - 427 (2007/10/03)
A variety of carbonyl compounds react with 2,2-dimethylpropane-1,3-diol in the presence of a catalytic amount of a novel yttria-zirconia based strong Lewis acid to afford the corresponding acetals in excellent yields.
Geminal Substituent Effects. VIII. Enthalpies of Formation od Acetals
Verevkin, Sergey P.,Dogan, Barbara,Haedrich, Johannes,Beckhaus, Hans-Dieter,Ruechardt, Christoph
, p. 93 - 98 (2007/10/02)
The standard enthalpies of combustion ΔHoc(1 or c) of the α-phenyl-substituted acetals (1) and diacetals (2) were measured calorimetrically.The enthalpies of vaporisation or sublimation ΔHvap or ΔHsub of 1-2 were obtained from the temperature function of the vapor pressure measured in a flow system, and the standard enthalpies of formation are obtained thereof: ΔH0f (l or c) and ΔHof (g) (in kJ mol-1 for 1a= -308.40+/-0.52(1), -248.94+/-0.88; 1b= -343.48+/-0.72(1), -288.5+/-1.5; 1c= -267.4+/-1.3(1), -205.3+/-1.3; 1d = -343.8+/-2.1 (c), -261.9+/-2.2; 1e = -397.02+/-0.86 ( c), -311.3+/-1.2; 1f = -414.52+/-0.80 (1), -350.68+/-0.86; 2a = -564.8+/-2.4 (c), -467.1+/-2.5; 2b = -547.6+/-1.6 (c), -414.9+/-2.7; 2c = -717.1+/-7.5 (c), -587.0+/-8.0.The results are combined into values of two strain free group increments CHPh> = -59.7 and CPh, C> = -71.3 kJ mol-1; and compared to the aliphatic series of acetals.
N-(arylmethyl)-2-(or -4)-cyanopyridinium hexafluoroantimonates as new useful catalysts for acetalization of carbonyl compounds
Lee,Lee,Takata,Endo
, p. 368 - 370 (2007/10/02)
Carbonyl compounds 1 were converted to the corresponding 1,3-dioxolanes 2 and 1,3-dioxanes 4 with ethylene glycol and 2,2-dimethyl-1,3-propandiol, respectively, in the presence of 1-3 mol% of N-(benzyl, 4-methylbenzyl or 4-methoxybenzyl)-2(or -4)cyanopyridinium hexafluoroantimonates 3. The catalyst 3d was also effective for the tetrahydropyranylation.
