Triethylammonium Hydrogen Sulfate [Et₃NH][HSO₄] as an Efficient Ionic Liquid Catalyst for the Synthesis of Coumarin Derivatives

A new method for the synthesis of diamantane by hydroisomerization of binor-S on treatment with sulfuric acid

“…The reaction of hydrocarbon 2 with hydrochloric acid proceeds with the addition of HCl to the cyclopropane ring and results in the formation of a mixture of mono- and dichloro derivatives, the synthesis of which has been reported [ 13 – 14 ]. When sulfuric acid is replaced by an ionic liquid prepared from triethylamine and sulfuric acid [ 15 ], the reaction follows a different route: Starting binor-S ( 2 ) is converted to two isomeric hexacyclic hydrocarbons, hexacyclo[8.4.0.0 2,7 .0 3,14 .0 4,8 .0 9,13 ]tetradec-5-ene ( 4а ) and hexacyclo[6.6.0.0. 2,6 .0 5,14 .0 7,12 .0 9,13 ]tetradec-3-ene ( 4b ), which are important precursors for the synthesis of triamantane [ 10 – 11 16 – 24 ] ( Scheme 4 ).…”

Recent Advances in the Synthesis of Coumarin Derivatives from Different Starting Materials

“…Yield of the obtained products were in the range 25-99%. The efficient Pechmann synthesis of coumarins, in the presence of triethylammonium hydrogen sulfate as a catalyst, was performed by Karimi-Jabei et al [105]. Optimization reaction between resorcinol and ethyl acetoacetate was conducted changing solvents (EtOH, MeOH, CHCl3, MeCN and solvent-free) and temperature (room temperature, 50 °C, 110 °C and 130 °C).…”

“…The efficient Pechmann synthesis of coumarins, in the presence of triethylammonium hydrogen sulfate as a catalyst, was performed by Karimi-Jabei et al [105]. Optimization reaction between resorcinol and ethyl acetoacetate was conducted changing solvents (EtOH, MeOH, CHCl 3 The efficient Pechmann synthesis of coumarins, in the presence of triethylammonium hydrogen sulfate as a catalyst, was performed by Karimi-Jabei et al [105]. Optimization reaction between resorcinol and ethyl acetoacetate was conducted changing solvents (EtOH, MeOH, CHCl3, MeCN and solvent-free) and temperature (room temperature, 50 °C, 110 °C and 130 °C).…”

Synthesis of coumarin derivatives in a microfluidic flow system employing the Pechmann condensation: A case study

“…Also reported was the use of an ionic liquid [Et 3 N(CH 2 ) 4 OSO 3 H][HSO 4 ] as the catalyst under solvent‐free conditions 20 . A facile and green methodology was documented using noncorrosive ionic liquid [Et 3 NH][HSO 4 ] as an efficient catalyst 21 . The methods have further been studied under solvent‐free conditions 22 .…”