Synthesis of enantiomerically enriched β-hydroxy selenides by catalytic asymmetric ring opening of meso-epoxides with (phenylseleno)silanes
作者:Marcello Tiecco、Lorenzo Testaferri、Francesca Marini、Silvia Sternativo、Francesca Del Verme、Claudio Santi、Luana Bagnoli、Andrea Temperini
DOI:10.1016/j.tet.2008.01.126
日期:2008.4
The first example of the enantioselectivering opening of meso-epoxides by (phenylseleno)silanes using salen(Cr)complexes as catalyst is described. This desymmetrization reaction constitutes a simple and convenient approach to synthetically versatile optically active β-hydroxy selenides.
<i>p</i>-Silylation of Arenes via Organic Photoredox Catalysis: Use of <i>p</i>-Silylated Arenes for Exclusive <i>o</i>-Silylation, <i>o</i>-Acylation, and <i>o</i>-Alkylation Reactions
Photocatalytic regiospecific p-silylation of arenes has been achieved by the coupling of in situ generated silyl radical with areneradicalcation. The strategy involves reductive activation of PhSe–SiR3 and single electron transfer from the electron rich arene to 9,10-dimethoxyanthracene radicalcation (DMA•+). p-Silyl arenes, thus formed, are further utilized for exclusive o-silylation reaction and