Selective synthesis of fluoroalkyl-containing multisubstituted benzenes through Co-mediated [2+2+2] cycloaddition reaction with fluoroalkylated alkynes
The reaction of various fluoroalkylated alkynes with 1.2 equiv of Co-2(CO)(8) in toluene at room temperature for 30 mm took place smoothly to give the corresponding alkyne-cobalt complex quantitatively. Without its purification, treatment of the in situ-generated complex with 6.0 equiv of various nonfluorinated alkynes at 130 degrees C for 4 h provided monofluoroallcylated multisubstituted benzenes in moderate to good yields. (C) 2015 Elsevier B.V. All rights reserved.
Rhodium-catalyzed [2+2+2] cycloaddition of various fluorine-containing alkynes—novel synthesis of multi-substituted fluoroalkylated aromatic compounds
Treatment of various fluorinated internal alkynes with 10 mol% of RhCl3·H2O and 30 mol% of i-Pr2NEt in toluene at the reflux temperature for 18 h gave the corresponding trimerization products as an isomeric mixture in high yields. Cycloaddition using 1.0 equiv. of fluorinated alkynes and 2.0 equiv. of non-fluorinated alkynes under the same reaction conditions as in the trimerization led to mono- and