The catalytic activity of 5,10,15,20‐tetrakis(4‐aminophenyl)porphyrinatotin(IV) trifluoromethanesulfonate, [SnIV(TNH2PP)(OTf)2], supported on chloromethylated MIL‐101, was investigated in the trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS) and also their tetrahydropyranylation with 3,4‐dihydro‐2H‐pyran. Excellent yields, mild reaction conditions, short reaction times and
P4VPy–CuO nanoparticles were synthesized using ultrasound irradiations. Relevant properties of the synthesized nanoparticles were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. After identification, the prepared reagent was used for the promotion of different types of protection reactions of alcohols, phenols and amines. Easy workup, short reaction times, excellent yields, relatively low cost and reusability of the catalyst are the striking features of the reported methods.
Chemoselective trimethylsilylation and tetrahydropyranylation of benzylic and primary and secondary aliphatic alcohols proceed efficiently in the presence of 1,3-dibromo-5,5-dimethylhydantoin (DBH) under mild and completely heterogeneous reaction conditions in excellent yields.
Supported N-propylsulfamic acid onto Fe3O4 magnetic nanoparticles as a reusable and efficient nanocatalyst for the protection/deprotection of hydroxyl groups and protection of aldehydes
作者:Amin Rostami、Bahman Tahmasbi、Fatemeh Abedi
DOI:10.1007/s11164-015-2239-3
日期:2016.4
nanocatalyst has been reported for the tetrahydropyranylation/depyranylation of a wide variety of alcohols and phenols by changing the solvent medium. Also, the protection of aldehydes as acylals using Ac2O in the presence of catalytic amount MNPs-PSA in good to high yields at room temperature undersolvent-freeconditions is described. After completing the reaction, the catalyst was easily separated from the
已经报道了负载在Fe 3 O 4磁性纳米颗粒(MNPs-PSA)上的 N- 丙基氨基磺酸作为一种有效的和可磁重复使用的纳米催化剂,可以通过改变溶剂介质将其用于多种醇和酚的四氢吡喃基化/脱吡喃基化。此外,还描述了在无溶剂条件下,在室温下,在催化量的MNPs-PSA存在下,使用Ac 2 O以高至高收率保护醛作为酰基的醛。反应完成后,借助外部磁场可以很容易地将催化剂从反应混合物中分离出来,并连续使用几次,而不会明显降低其催化效率。
Silica Triflate as a New, Mild and Efficient Catalyst for Tetrahydropyranylation of Alcohols and Deprotection of Tetrahydropyranyl Ethers
作者:F. Shirini、K. Marjani、H. Taherpour Nahzomi
DOI:10.1080/10426500701407839
日期:2007.7.19
Silica triflate, a new stable derivative of silica gel, is easily prepared by the reaction of silica gel with trifluoromethanesulfonyl chloride. Silica triflate acts as a highly effective and reusable catalyst for tetrahydropyranylation of alcohols and deprotection of tetrahydropyranylethers under mild and completely heterogeneous reaction conditions.