TfOH/DMEDA-Mediated Cyclization of 2-(3-Arylthioureido)- amide to Form 2-Thioimidazoline-4-ones

摘要

A synthetic methodology for a series of 2-thioimidazoline-4- ones (4a–4u) was developed using trifluoromethanesulfonic acid (TfOH)/N,N’-dimethylethylenediamines (DMEDA) in di- chloromethane. α-Aminoacetamides and isothiocyanates were used to prepare 2-(3-arylthiourea)amide (3a–3u), which was cyclized to produce the desired 2-thioimidazoline-4-ones with good to excellent yield (75%-95%). All the new compounds obtained were characterized by ~1 HNMR, ~(13) CNMR and HRMS, and further corroborated by X-ray crystallography for 4i, 4o, 4p.