Allyl Isothiocyanate → Ethylenediamine

Participants

Reaction Steps

Other suitable reducing agents include lithium aluminum hydride. Treatment of 3-phenyl-1,2-diaminopropane with 1,1′-thiocarbonyldiimidazole rapidly produced 4-benzyl-2-imidazolidinethione 4. The yield was 90%, which is essentially quantitative since the starting material was about 90% pure. Most of the 2-imidazolidinethiones were prepared in good yields with 1,1′-thiocarbonyldiimadazole. However, the less expensive allyl isothiocyanate was also found to be an excellent reagent for the conversion of vicinal diamines to 2-imidazolidinethiones. The parent compound, 2-imidazolidinethione, was obtained in 91% yield from 1,2-diaminoethane and allyl isothiocyanate in refluxing bromobenzene. These conditions converted 2-thienyl-1,2-diaminoethane to the corresponding 2-imidazolidinethione, 36J, in 83% yield.

Provenance & Evidence