Benzo thiophene-3-boronic acid

The electron-rich thiophene ring system can be elaborated into complex, fused thiophenes by acid-mediated intramolecular annelation reactions. For example, treatment of alcohol 96 with trimethylsilyl triflate promoted a Friedel-Crafts acylation and subsequent dehydration giving benzo[b]thiophene 97, a potential analgesic <00JMC765>. Treatment of ketone 98 with p-toluenesulfonic acid resulted in the formation of fused benzo[b]thiophene 99 <00T8153>. Another variant involved the cyclization of epoxide 100 to fused benzo[f>]thiophene 101 mediated by boron trifluoride-etherate . [Pg.95]

Preparation of 2-benzo[6]thienyl-lithium followed by its reaction with butyl borate and oxidation of the intermediate boronic acid derivative has been used for the synthesis of the 2-hydroxybenzo[6]thiophen system (thio-... [Pg.447]

Benzo[b]thiophene-2-boronic acid AmpC P-lactamase 27 107,108... [Pg.496]

When 2-hydroxymethyl-5,6-methylenedioxybenzo[6]thiophene is heated in a polar solvent with a catalytic amount of mineral acid, the polycyclic compound (166) is formed in 75% yield, probably by way of the intermediate (251).190 3-Hydroxymethylbenzo[6]thiophene and di(3-benzo[6]thienyl)methane react together in the presence of boron trifluoride to give a compound with the probable structure 252.486... [Pg.314]

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