An efficient method for the silylation of hydroxyl groups with hexamethyldisilazane (HMDS) catalyzed by aluminum tris(dihydrogen phosphate) under solvent-free and ambient conditions
A highly efficient and mild procedure for the trimethylsilylation of a wide variety of alcohols, including primary, benzylic, secondary, hindered secondary, tertiary, phenols, and oximes with hexamethyldisilazane (HMDS), using Al(H2PO4)3 as a recyclable heterogeneous catalyst at room temperature in a few minutes with excellent yields under solvent-free conditions is described.Key words: trimethylsilylation
Extremely facile and efficient procedures have been developed for the synthesis of highlyfunctionalizedpiperidines and dihydro-2-oxypyrroles via one-pot multi-component reactions in the presence of Al(H2PO4)3 as a heterogeneous and eco-friendly catalyst under mild conditions. The multi-component reaction of aromatic aldehydes, aromatic amines, and β-keto esters catalyzed by Al(H2PO4)3 in EtOH at room
在Al(H 2 PO 4)3作为非均相和生态友好型催化剂的存在下,通过单锅多组分反应合成高度官能化的哌啶和二氢-2-氧基吡咯的方法极为简便有效。温和的条件。Al(H 2 PO 4)3催化的芳香醛,芳香胺和β-酮酯的多组分反应在室温下,在乙醇中提供高官能度的哌啶,收率良好至极佳。这些功能化的哌啶的结构和相对立体化学通过单X射线晶体学分析证实。发现相同的催化剂可用于在环境温度下使用胺,乙炔二羧酸二烷基酯和甲醛在甲醇中的四组分反应来合成多官能化的二氢-2-氧基吡咯。发现该催化剂是可回收的,并且可以使用多达五次而不会显着降低其活性。
Al(H<sub>2</sub>PO<sub>4</sub>)<sub>3</sub> as an efficient and recyclable catalyst for the one-pot synthesis of naphthopyranopyrimidines
作者:Seyed Sajad Sajadikhah
DOI:10.1039/c5ra00679a
日期:——
An efficient one-pot protocol has been developed for the synthesis of naphthopyranopyrimidine derivatives via a three-component reaction of aromatic aldehydes, β-naphthol and 6-amino-1,3-dimethyl uracil in the presence of Al(H2PO4)3.
resonance spectroscopy. Crystalline aluminum phosphate products and amorphous material were identified using this technique. α-alumina and heat-treated alumina-gel that were reacted with phosphate in an Al:P ratio of 1:1 yielded dramatically different aluminum orthophosphate:aluminum metaphosphate product ratios of 8.2:1 and 1:1.1, respectively. When alumina-gel was heat-treated with phosphate, an abundance
Triazine compounds containing phosphorous as flame retardants
申请人:Dave Trupti
公开号:US09200122B2
公开(公告)日:2015-12-01
The present invention relates to phosphorus-containing triazine compounds of the formula (I) and (III) and to the polymers obtainable from the water-eliminating polycondensation of a compound of the formula (II), and to the use thereof as flame retardants.