The 2-thiomethylbenzofuran derivatives 3 are conveniently prepared in good yields through the reactions between the readily available 2-methylene-2,3-dihydrobenzofuran-3-ols 1 and the thiol derivatives 2 (including alkyl thiols, thiophenol, and thioacetic acid). The allylic substitution process may be either acid-catalysed or promoted by radical initiators. In the first case, the reactions are carried out at 90 °C in 1,2-dimethoxyethane (DME) as the solvent in the presence of H2SO4 as the proton source. The radical-promoted reactions take place in DME at 90 °C in the presence of azobis(isobutyronitrile) (AIBN) or benzoyl peroxide (BP) as the radical initiator.
Acid-catalysed or radical-promoted allylic substitution of 2-methylene-2,3-dihydrobenzofuran-3-ols with thiol derivatives: a novel and expedient synthesis of 2-(thiomethyl)benzofurans
GABRIELE, Bartolo;MANCUSO R;
2010-01-01
Abstract
The 2-thiomethylbenzofuran derivatives 3 are conveniently prepared in good yields through the reactions between the readily available 2-methylene-2,3-dihydrobenzofuran-3-ols 1 and the thiol derivatives 2 (including alkyl thiols, thiophenol, and thioacetic acid). The allylic substitution process may be either acid-catalysed or promoted by radical initiators. In the first case, the reactions are carried out at 90 °C in 1,2-dimethoxyethane (DME) as the solvent in the presence of H2SO4 as the proton source. The radical-promoted reactions take place in DME at 90 °C in the presence of azobis(isobutyronitrile) (AIBN) or benzoyl peroxide (BP) as the radical initiator.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
