Sulfuric Acid → Methyl 3-thioureidobenzoate

Participants

Reaction Conditions

Reaction Steps

At −10° C. sulfuric acid (0.46 mL) is added dropwise to a solution of methyl 3-aminobenzoate (17.2 mmol) in chlorobenzene (19 mL). After 15 min KSCN (18.2 mmol) is added portionwise over 30 min. The mixture is treated with 18-crown-6, heated to 100° C. for 16 h and allowed to cool to RT. After 4 h the obtained precipitate is filtered off and washed successively with chlorobenzene (33 mL) and hexane (three times 130 mL). The residue is diluted with water (390 mL) and the suspension is stirred for 30 min. After filtration the residue is washed twice with water (130 ml, each), concentrated in vacuo and dried additionally by azeotropic removal of water with toluene. The obtained product is used without further purification.

Provenance & Evidence