Guanidine Hydrochloride → HCID 178431914, compound

Participants

Reaction Steps

A mixture of guanidine hydrochloride (14.33 g), and 50% aqueous NaOH (10.00 g) in THF (250 ml) is stirred at room temperature overnight. THF (250 ml), and anhydrous Na2SO4 (7.5 g) are added to the mixture and stirring continued for 1 hour. A solution of 2-chloro-3-isocyanato-4-methylthiophene (8.68 g) in THF (500 ml) is added dropwise to the stirred mixture. After the addition is complete, stirring is continued for 30 minutes. The solvent is decanted, leaving a THF insoluble material. The solvent is evaporated under reduced pressure. The evaporated residue is suspended in 500 ml of 2% aqueous HCl and added to the THF insoluble material. This mixture is stirred vigorously with 250 ml of Et2O for 30 minutes. Insoluble material is separated by decantation. The aqueous layer is separated, washed with Et2O and alkalinized with NaHCO3, forming a precipitate. The precipitate is washed with H2O and air dried to afford 8.85 g of a tan crystalline solid. The tan solid is dissolved in 5% aqueous HCl (175 ml), filtered through Celite, and the filtrate cooled rapidly to room temperature. After standing overnight in the cold, the precipitate is collected, washed with a portion of the mother liquor, dried in vacuo, and stirred in 100 ml of CH2Cl2, and air dried in vacuo (50° C.) overnight to yield 7.20 g of the amidinourea hydrochloride as a tan powder, m.p. 173°-174.5° C. w/dec.

Provenance & Evidence