Magnetic Fe<sub>3</sub>O<sub>4</sub>@silica sulfuric acid nanoparticles promoted regioselective protection/deprotection of alcohols with dihydropyran under solvent-free conditions
Protection (and deprotection) of hydroxylgroups via tetrahydropyranylation was carried out effectively using a catalytic amount of Fe3O4 supportedsilica sulphuric acid nanoparticles (Fe3O4@SiO2@SO3H) under solvent-free conditions. The synthesized nanocatalyst was characterized by XRD, TEM, FT-IR etc. A wide range of tetrahydropyranylated alcohol derivatives were synthesized using this heterogeneous
在无溶剂条件下,使用催化量的Fe 3 O 4负载的二氧化硅硫酸纳米颗粒(Fe 3 O 4 @SiO 2 @SO 3 H)有效地进行了通过四氢吡喃基化进行的羟基保护(和脱保护)。通过XRD,TEM,FT-IR等对合成的纳米催化剂进行了表征。使用这种多相磁性纳米催化剂,可以在10–20分钟内以高收率合成各种四氢吡喃基化的醇衍生物。另外,也可以使用相同的催化剂在MeOH存在下将四氢吡喃基醚脱保护为母体醇化合物。反应完成后,使用外部磁体很容易将催化剂从反应介质中分离出来,从而改善了整个合成过程。回收催化剂并将其再用于五个连续的反应中,而没有任何明显的活性损失。温和的反应条件,操作简便,无溶剂的条件,高选择性,磁性纳米催化剂的易回收性和高收率可被视为我们程序的优势。
Highly selective tetrahydropyranylation/dehydropyranylation of alcohols and phenols using porous phenolsulfonic acid-formaldehyde resin catalyst under solvent-free condition
solvent-free chemoselective tetrahydropyranylation/depyranylation of alcohols and phenols is reported herein using mesoporous Phenolsulfonic Acid Formaldehyde Resins as a heterogeneous acidcatalyst. The catalyst successfully performed chemoselective protection and deprotection reactions of a wide range of substrates ranging from primary to secondary and tertiary alcohols and also phenols. The reactions were