Microwave-assisted efficient synthesis of 2-arylbenzo[b]furans
and 2-ferrocenylbenzo[b]furans from readily prepared
propargylic alcohols and o-iodophenols
LIANSHENG WU, XIAOKANG SHI, XIAOYUN XU, FEN LIANG and GUOSHENG HUANG*
State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, P. R. of China
MS received 14 September 2010; revised 18 May 2011; accepted 27 June 2011
Abstract. A simple, efficient and expeditious method for synthesis of 2-arylbenzo[b]furans and 2-
ferrocenylbenzo[b]furans from readily prepared propargylic alcohols, o-iodophenols and silica gel with the
catalyst of PdCl2(PPh3)2 (2 mol%)/CuI (2mol%) and microwave-promoted Sonogashira coupling/cyclization
reaction is developed. The methodology can produce good to excellent yields. In addition, this method can also
be completed in one-pot with iodobenzene, 2-methyl-3-butyn-2-ol and 2-iodo-4-methylphenol as reactants.
Graphical Abstract. A simple and efficient method for synthesis of 2-arylbenzo[b]furnas and 2-
ferrocenylbenzo[b]furans has been developed from the Sonogashira coupling/
cyclization reaction of propargylic alcohols and o-iodophenols in the presence
of silica gel and catalytic amounts of PdCl2(PPh3)2 (2 mol%) and CuI (2 mol%)
under microwave conditions.
Keywords. Benzo[b]furan; o-iodophenol; propargylic alcohols; microwave irradiation.