Ethanol → HCID 12424623, compound

Participants

Reaction Steps

Potassium acetate (1.3 g., 12.5 mmoles) was dissolved in 40 ml. of an aqueous ethanol mixture (1:1). With stirring, thiosemicarbazide (1.1 g., 12.5 mmoles) and ethyl 4-chloroacetoacetate (2.0 g., 12.5 mmoles) were introduced. After 3 hours of stirring at room temperature a red oil settled out. The reaction mixture was diluted with water and extracted several times with methylene chloride (total 100 ml.). Combined extracts were dried (calcium chloride), filtered, and concentrated under reduced pressure to approximately 2.0 g. of oily residue. Thin layer chromatography (chloroform) revealed the presence of two compounds. This oil was then chromatographed on a silica gel column using methylene chloride as the eluent. Compound IVA (see Example 12) was in the first few fractions while the latter fractions contained a single component (0.6 g.) characterized as Compound IIA by pmr. Although Compound IIA was chromatographically pure, it would not crystallize; ir (mull): 3450-3200 (N--H), 1725 (C=O), 1620, 1580 (C=N) cm-1 : pmr (deuteriochloroform): δ1.20 (t, 3H, CH3), 3.55 (s, 2H, CH2CO), 4.15 (q, 2H, OCH2), 5.80-6.20 (s-broad, 3H, NH), 6.30 (s, 1H, vinyl); ms: (m/e)201(M+).

Provenance & Evidence