Highly Chemoselective Esterification Reactions and Boc/THP/TBDMS Discriminating Deprotections under Samarium(III) Catalysis
摘要:
The usefulness of SmCl(3) as an excellent catalyst for chemoselective esterifications and selective removal of acid sensitive protecting groups such as Boc, THP, and TBDMS in the presence of one another is demonstrated through suitable examples.
THP ethers were formed cleanly during photolysis of 3,4dihydro-2H-pyran, an alcohol, and catalytic 1,5-dichloro-9, 10-anthraqui none with use of visible light. The reaction could be conducted under ambient fluorescent lighting or with sunlight as well as in a Rayonet reactor. The scope and mechanism are discussed.
Highly Chemoselective Esterification Reactions and Boc/THP/TBDMS Discriminating Deprotections under Samarium(III) Catalysis
The usefulness of SmCl(3) as an excellent catalyst for chemoselective esterifications and selective removal of acid sensitive protecting groups such as Boc, THP, and TBDMS in the presence of one another is demonstrated through suitable examples.
Arylazo Sulfones as Nonionic Visible-Light Photoacid Generators
作者:Lorenzo Di Terlizzi、Angelo Martinelli、Daniele Merli、Stefano Protti、Maurizio Fagnoni
DOI:10.1021/acs.joc.2c01248
日期:——
The selective visible-light-driven generation of a weak acid (sulfinic acid, in nitrogen-purged solutions) or a strong acid (sulfonic acid, in oxygen-purged solutions) by using shelf-stable arylazo sulfones was developed. These sulfones were then used for the green, smooth, and efficient photochemical catalytic protection of several (substituted) alcohols (and phenols) as tetrahydropyranyl ethers or