Indium Tribromide as a Highly Efficient and Versatile Catalyst for Chemoselective Synthesis of Acylals from Aldehydes under Solvent-Free Conditions
作者:Yong-Mei Wang、Liang Yin、Zhan-Hui Zhang、Mei-Li Pang
DOI:10.1055/s-2004-829549
日期:——
A mild and efficient method has been developed for the chemoselective preparation of acylals from aldehydes in the presence of catalytic amounts (0.01-1.0 mol%) of InBr3 under solvent-free conditions in very good to excellent yields.
Zinc Tetrafluoroborate-Catalyzed Efficient Conversion of Aldehydes to Geminal Diacetates and Cyanoacetates
作者:Brindaban C. Ranu、Jyotirmoy Dutta、Arijit Das
DOI:10.1246/cl.2003.366
日期:2003.4
A trace of an aqueous solution of zinc tetrafluoroborate was demonstrated to catalyze the conversion of an aldehyde to its 1,1-diacetate by acetic anhydride without any solvent. A similar reaction of an aldehyde with a mixture of potassium cyanide and acetic anhydride in methylene chloride was also catalyzed by Zn(BF4)2 to provide the corresponding geminal cyanoacetate.
Iron(III) tosylate catalyzed acylation of alcohols, phenols, and aldehydes
作者:Neil J. Baldwin、Anna N. Nord、Brendan D. O’Donnell、Ram S. Mohan
DOI:10.1016/j.tetlet.2012.10.033
日期:2012.12
Iron(III) p-toluenesulfonate (tosylate) is an efficient catalyst for acetylation of alcohols, phenols, and aldehydes. The acetylation of 1° and 2° alcohols, diols, and phenols proceeded smoothly with 2.0 mol % of catalyst. However, the reaction worked well with only a few 3° alcohols. The methodology was also applicable to the synthesis of a few benzoate esters but required the use of 5.0 mol % catalyst
Solvent-free catalytic preparation of 1,1-diacetates from aldehydes using a Wells–Dawson acid (H6P2W18O62·24H2O)
作者:Gustavo P. Romanelli、Horacio J. Thomas、Graciela T. Baronetti、Juan C. Autino
DOI:10.1016/s0040-4039(02)02817-4
日期:2003.2
Aromatic and aliphatic aldehydes are transformed in 1,1-diacetates (acylals) in mild conditions, by a treatment with acetic anhydride and a Wells–Dawson acid (H6P2W18O62·24H2O). gem-Diacetylation proceeds in Ac2O with a little as 1% mol Wells–Dawson acid at room temperature and under solventless conditions, obtaining very good to excellent yields (88–98%) of 1,1-diacetates (19 examples). Neither 4
通过用乙酸酐和韦尔斯道森酸(H 6 P 2 W 18 O 62 ·24H 2 O)处理,可以在温和的条件下将芳香族和脂肪族醛转化为1,1-二乙酸酯(酰基)。在室温和无溶剂条件下,用少量的1%mol Wells-Dawson酸在Ac 2 O中进行宝石二乙酰化反应,获得1,1-二乙酸酯的非常好至极好的收率(88-98%)(19个实例)。4-二甲基氨基苯甲醛和酮都不会在相同条件下反应。
Cerium(IV) Triflate‐Catalyzed Selective <i>Gem</i>‐diacetylation of Aldehydes with Acetic Anhydride
作者:J. W. John Bosco、Anil K. Saikia
DOI:10.1080/00397910701649106
日期:2007.12.1
Abstract It has been observed that a catalytic amount (0.1 mol%) of cerium(IV) triflate afforded geminal diacetates from aldehydes with acetic anhydride in toluene at ambient temperature. Ketones are not affected under these reaction conditions. The reaction is rapid and mild with good to high yields.