Cu-catalyzed reaction of 1,2-dihalobenzenes with 1,3-cyclohexanediones for the synthesis of 3,4-dihydrodibenzo[b,d]furan-1(2H)-ones.
The Cu(I)-catalyzed reaction of 1-bromo-2-iodobenzenes and other 1,2-dihalobenzenes with 1,3-cyclohexanediones in DMF at 130 °C using Cs(2)CO(3) as a base and pivalic acid as an additive selectively delivers 3,4-dihydrodibenzo[b,d]furan-1(2H)-ones with yields ranging from 47 to 83%. The highly regioselective domino process is based on an intermolecular Ullmann-type C-arylation followed by an intramolecular Ullmann-type O-arylation. Substituted products are accessible by employing substituted 1-bromo-2-iodobenzenes and substituted 1,3-cyclohexanediones as substrates. Reaction with an acyclic 1,3-diketone yields the corresponding benzo[b]furan.
Bioorganische Chemie, Institut für Chemie, Universität Hohenheim, Garbenstrasse 30, D-70599 Stuttgart, Germany.
Nayyef
N
Aljaar
Chandi C
CC
Malakar
Jürgen
J
Conrad
Sabine
S
Strobel
Thomas
T
Schleid
Uwe
U
Beifuss
D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D003510:Cyclohexanes / Q000737:chemistry*; D006846:Hydrocarbons, Halogenated / Q000737:chemistry*; D007462:Iodobenzenes / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
D001572:Benzofurans; D003510:Cyclohexanes; D006846:Hydrocarbons, Halogenated; D007462:Iodobenzenes; D007659:Ketones; D003300:Copper