Efficient synthesis of β-hydroxy thiocyanates from epoxides and ammonium thiocyanate using 1,4-bis(triphenylphosphonium)-2-butene dichloride as a new catalyst

1,4-bis(triphenylphosphonium)-2-butene dichloride was developed as a new phase transfer catalyst. This quaternized phosphonium salt catalyzed the regioselective ring opening of epoxides by thiocyanate ion to give β-hydroxy thiocyanates in high yields under mild conditions.