摘要:
1,4-Diphenyl- and 1,4-bis(4-chlorophenyl)-1,4-butanediones (3 and 4), as well as 1-phenyl-, 1-(4-chlorophenyl)-, and 1-(4-methoxyphenyl)-1,4-pentanediones (7-9) react with bis(tributyltin), bis(tricyclohexyltin), and/or bis(triphenyltin) sulfide in the presence of boron trichloride to give, 2,5-diaryl- or 5-methyl-2-arylthiophenes. 1,8-Diphenyl-1,7-octadiyne-3,6-dione (10) and 1-phenyl-1,7-nonadiyne-3,6-dione (11), which were prepared in nine steps from 1,4-butanediol, react with the thionation reagents to give 2,5-bis(2-phenylethynyl)thiophene (20g) and 2-(2-phenylethynyl)-5-(1-propynyl)thiophene (20f), respectively.