2-(ortho-Hydroxyphenyl)-alkynethiolates and -selenolates, obtained through
base catalyzed ring cleavage of 4-(ortho-hydroxy phenyl)-1,2,3-thiadiazoles
and -1,2,3-selenadiazoles, smoothly transform into 2-benzofuranthiolates a
nd -selenolates. These reactive intermediates can be alkylated in high yiel
d. This reaction sequence could be applied to the synthesis of electron ric
h thiacrown ethers. The 2-(ortho-aminophenyl)-alkynethiolate analogously fo
rms 2-methylsulfanylindole. (C) 2000 Elsevier Science Ltd. All rights reser
ved.