4,5-dihydro-1,3-thiazol-2-amine;hydrochloride

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Reaction of diethyl oxalate (7.66 g, 52.4 mmol), ethyl benzyloxyacetate (10.2 g, 52.5 mmol) and sodium hydride (2.31 g of a 60% dispersion in mineral oil, 57.9 mmol) with 2-amino-2-thiazoline hydrochloride (7.28 g, 52.5 mmol) as described in intermediate 1 gave 7.99 g (46% yield) of the title ester as white crystals; mp 117 118° C. 1HNMR 400 MHz (CDCl3) δ (ppm): 1.32 (3H, t, J=7.1 Hz, CH3), 3.52 (2H, t, J=7.6 Hz, CH2), 4.34 (2H, q, J=7.1 Hz, OCH2), 4.49 (2H, t, J=7.6 Hz, CH2), 5.22 (2H, s, OCH2), 7.3–7.51 (5H, m, aromatics). Anal. Calcd for C16H16N2O4S: C, 57.81; H, 4.85; N, 8.42. Found: C, 57.78; H, 4.76; N, 8.30.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Reaction of diethyl oxalate (7.66 g, 52.4 mmol), ethyl benzyloxyacetate (10.2 g, 52.5 mmol) and sodium hydride (2.31 g of a 60% dispersion in mineral oil, 57.9 mmol) with 2-amino-2-thiazoline hydrochloride (7.28 g, 52.5 mmol) as described in intermediate 1 gave 7.99 g (46% yield) of the title ester as white crystals; mp 117 118° C. 1HNMR 400 MHz (CDCl3) δ (ppm): 1.32 (3H, t, J=7.1 Hz, CH3), 3.52 (2H, t, J=7.6 Hz, CH2), 4.34 (2H, q, J=7.1 Hz, OCH2), 4.49 (2H, t, J=7.6 Hz, CH2), 5.22 (2H, s, OCH2), 7.3–7.51 (5H, m, aromatics). Anal. Calcd for C16H16N2O4S: C, 57.81; H, 4.85; N, 8.42. Found: C, 57.78; H, 4.76; N, 8.30.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Reaction of diethyl oxalate (7.66 g, 52.4 mmol), ethyl benzyloxyacetate (10.2 g, 52.5 mmol) and sodium hydride (2.31 g of a 60% dispersion in mineral oil, 57.9 mmol) with 2-amino-2-thiazoline hydrochloride (7.28 g, 52.5 mmol) as described in intermediate 1 gave 7.99 g (46% yield) of the title ester as white crystals; mp 117 118° C. 1HNMR 400 MHz (CDCl3) δ (ppm): 1.32 (3H, t, J=7.1 Hz, CH3), 3.52 (2H, t, J=7.6 Hz, CH2), 4.34 (2H, q, J=7.1 Hz, OCH2), 4.49 (2H, t, J=7.6 Hz, CH2), 5.22 (2H, s, OCH2), 7.3–7.51 (5H, m, aromatics). Anal. Calcd for C16H16N2O4S: C, 57.81; H, 4.85; N, 8.42. Found: C, 57.78; H, 4.76; N, 8.30.