arenes and 2,2-dimethylchromans using a Friedel–Crafts-type coupling between activated arenes and isoprene is reported. A combination of catalytic amounts of FeCl3 and AgBF4 promotes a regioselective prenylation event followed by a cyclization to form a 2,2-dimethylchroman structure. The method avoids isoprene polymerization and allows the facile late-stage derivatization of biologically active motifs.
Mesoporous and hexagonally ordered CuAl-SBA-15-catalyzed tandem C–C and C–O bond formation between phenols and allylic alcohols
作者:Shaji Varghese、Chokkalinkam Anand、Dattatray Dhawale、Ajayan Mano、Veerappan V. Balasubramanian、George Allen Gnana Raj、Samuthira Nagarajan、Mohammad A. Wahab、Ajayan Vinu
DOI:10.1016/j.tetlet.2012.08.043
日期:2012.10
A novel mesoporous catalyst, CuAl-SBA-15, with a hexagonally ordered porous structure prepared via a soft-templating approach in a highly acidic medium is used for tandemC–C and C–Obondformationbetweenphenols and allylic alcohols to afford a variety of dihydrobenzopyrans in good yields. The catalyst is also found to be highly active for the synthesis of vitamin E and can be recycled several times
The present invention relates to compounds of formula I:
or a pharmaceutically acceptable salt or mixtures thereof that inhibit serine protease activity, particularly the activity of hepatitis C virus NS3-NS4A protease.
Synthesis of Chromans via [3 + 3] Cyclocoupling of Phenols with Allylic Alcohols Using a Mo/<i>o</i>-Chloranil Catalyst System
作者:Yoshihiko Yamamoto、Kouhei Itonaga
DOI:10.1021/ol802800s
日期:2009.2.5
The combination of a molybdenum complex (CpMoCl(CO)(3) or [CpMo(CO)(3)](2)) and o-chloranil was used as a catalyst in the [3 + 3] cyclocoupling of phenols and allylic alcohols under microwave heating conditions. Substituted chromans were selectively obtained in moderate to good isolated yields.