Hafnium Triflate as a Highly Potent Catalyst for Regio- and Chemoselective Deprotection of Silyl Ethers
Xiu-An Zheng, Rui Kong, Hua-Shan Huang, Jing-Ying Wei, Ji-Zong Chen, Shan-Shan Gong*, Qi Sun*
*Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, 605 Fenglin Avenue, Nanchang, Jiangxi 330013, P. R. of China, Email: gongshanshanjxstnu.edu.cn, sunqijxstnu.edu.cn
X.-A. Zheng, R. Kong, H.-S. Huang, J.-Y. Wei, J.-Z. Chen, S.-S. Gong, Q. Sin, Synthesis, 2019, 51, 944-952.
DOI: 10.1055/s-0037-1610307
Abstract
Hf(OTf)4 exhibits exceptionally high potency in desilylations. Since the amounts of Hf(OTf)4 required for the deprotection of 1°, 2°, 3° alkyl and aryl tert-butyldimethylsilyl (TBS) ethers range from 0.05 mol% to 3 mol%, a regioselective deprotection can be achieved. A chemoselective cleavage of different silyl ethers or removal of TBS in the presence of most hydroxyl protecting groups was also accomplished.
see article for more examples
Key Words
hafnium triflate, desilylation, regioselectivity, chemoselectivity, tert-butyldimethylsilyl ethers
ID: J66-Y2019