One-pot synthesis of benzo[b]thiophenes and benzo[b]selenophenes from o-halo-substituted ethynylbenzenes: convenient approach to mono-, bis-, and tris-chalcogenophene-annulated benzenes.
A convenient one-pot procedure for the synthesis of benzo[b]thiophenes and selenophenes from readily available o-halo-ethynylbenzene precursors is described. Regardless of the substituent on the acetylene terminus or the number of cyclization moieties on the precursors, various benzo[b]thiophenes and selenophenes, including not only the parent, alkyl-, and phenyl-substituted derivatives but also benzo[1,2-b:4,5-b']dithiophenes and diselenophenes and benzo[1,2-b:3,4-b':5,6-b'']trithiophenes and triselenophenes can be prepared in good to high yields.
Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan.
Tomoya
T
Kashiki
Shoji
S
Shinamura
Masahiro
M
Kohara
Eigo
E
Miyazaki
Kazuo
K
Takimiya
Masaaki
M
Ikeda
Hirokazu
H
Kuwabara
D000114:Acetylene / Q000031:analogs & derivatives* / Q000737:chemistry; D001555:Benzene Derivatives / Q000737:chemistry*; D003500:Cyclization; D006846:Hydrocarbons, Halogenated / Q000737:chemistry*; D015394:Molecular Structure; D016566:Organoselenium Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013876:Thiophenes / Q000138:chemical synthesis* / Q000737:chemistry
D001555:Benzene Derivatives; D006846:Hydrocarbons, Halogenated; D016566:Organoselenium Compounds; D013876:Thiophenes; C088015:benzothiophene; C044736:phenylacetylene; D000114:Acetylene