amount of InCl3 and aceticanhydride remarkably promotes the Knoevenagel condensation of a variety of aldehydes and activated methylene compounds. This catalytic system accommodates aromatic aldehydes containing a variety of electron-donating and -withdrawing groups, heteroaromatic aldehydes, conjugate aldehydes, and aliphatic aldehydes. Central to successfully driving the condensation series is the formation
A Facile and Efficient Conversion of Aldehydes into 1,1-Diacetates (Acylals) using Iron(III) Fluoride as a Novel Catalyst
作者:V. T. Kamble、R. A. Tayade、B. S. Davane、K. R. Kadam
DOI:10.1071/ch06166
日期:——
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
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.
simple and efficient procedure for the preparation of silica‐bonded propyl‐diethylene‐triamine‐N‐sulfamic acid (SPDTSA) by reaction of 3‐diethylenetriamine‐propylsilica (DTPS) and chlorosulfonic acid in chloroform is described. Silica‐bonded propyl‐diethylene‐triamine‐N‐sulfamic acid is employed as a recyclable catalyst for the synthesis of 1,1‐diacetates from aromatic aldehydes and acetic anhydride under
Thallium(III) Chloride: A Mild
and Efficient Catalyst for Acylation of Alcohols, Phenols
and Thiols, and for Geminal Diacylation of Aldehydes under
Solvent-Free Conditions
作者:Sung Kim、Santosh Kadam
DOI:10.1055/s-0028-1083148
日期:——
simple and efficientcatalyst for acylation of alcohols, phenols and thiols. It is also very effective for geminal diacylation of aldehydes. The acylation reaction using acetic anhydride proceeds in excellent yield in the presence of catalytic amounts ofthallium(III) chloride (1 mol%) at room temperature within relatively short reaction times (<20 min). Structurally diverse alcohols, phenols, thiols and