Preparation, characterization and use of 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate as an eco-benign, efficient and reusable ionic liquid catalyst for the chemoselective trimethylsilyl protection of hydroxyl groups
作者:Nader Ghaffari Khaligh
DOI:10.1016/j.molcata.2011.08.021
日期:2011.10
New and novel ionic liquid (3-methyl-1-sulfonic acid imidazolium hydrogen sulfate) is a recyclable and eco-benign catalyst for the chemoselective trimethylsilyl protection of hydroxyl groups under solvent-free conditions to afford trimethylsilanes in excellent yields (92-100%) and in very short reaction times (1-8 min). The catalyst was characterized by FT-IR, H-1 NMR and C-13 NMR studies. All the products were extensively characterized by H-1 NMR, IR, GC-MS and melting point analyses. A mechanism for the catalytic activity is proposed. The catalyst can be recovered and reused without loss of activity. The work-up of the reaction consists of a simple separation, followed by concentration of the crude product and purification. (C) 2011 Elsevier B.V. All rights reserved.
Succinimide-<i>N</i>-Sulfonic Acid: A Mild, Efficient, and Reusable Catalyst for the Chemoselective Trimethylsilylation of Alcohols and Phenols
作者:F. Shirini、N. Ghaffari Khaligh
DOI:10.1080/10426507.2011.602377
日期:2011.11.1
Poly(4-vinylpyridine) catalyzed chemoselective O-TMS protection of alcohols and phenols and N-Boc protection of amines
作者:Farhad Shirini、Nader Ghaffari Khaligh
DOI:10.1007/s13738-011-0060-5
日期:2012.8
Poly(4-vinylpyridine) (PVP) acts as an efficient and reusable catalyst for the selective and efficient trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS) and N-tert-butoxycarbonylation of amines with (Boc)2O. All reactions were performed under mild conditions in good to high yields.