ethyl 2-hydrazinylacetate

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of compound 44 (4 g, 14.0 mmol), ethyl 2-hydrazinylacetate (2.37 g, 15.0 mmol) and methanol (60 mL) was heated for 1.5 h. The reaction mixture was cooled to 0° C. and solvent was removed under reduced pressure. Water (100 mL) was added and the reaction mixture extracted with ethyl acetate (50 mL×3). Combined organic layer was washed with brine, dried over sodium sulphate and concentrated under reduced pressure. The crude compound was purified by column chromatography using 10% ethyl acetate in n-hexane as an eluent to afford the separated isomer 45 (1.2 g, 24%). was heated for 1.5 h solvent was removed under reduced pressure Water (100 mL) was added the reaction mixture extracted with ethyl acetate (50 mL×3) Combined organic layer was washed with brine dried over sodium sulphate concentrated under reduced pressure The crude compound was purified by column chromatography

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of compound 44 (4 g, 14.0 mmol), ethyl 2-hydrazinylacetate (2.37 g, 15.0 mmol) and methanol (60 mL) was heated for 1.5 h. The reaction mixture was cooled to 0° C. and solvent was removed under reduced pressure. Water (100 mL) was added and the reaction mixture extracted with ethyl acetate (50 mL×3). Combined organic layer was washed with brine, dried over sodium sulphate and concentrated under reduced pressure. The crude compound was purified by column chromatography using 10% ethyl acetate in n-hexane as an eluent to afford the separated isomer 45 (1.2 g, 24%). was heated for 1.5 h solvent was removed under reduced pressure Water (100 mL) was added the reaction mixture extracted with ethyl acetate (50 mL×3) Combined organic layer was washed with brine dried over sodium sulphate concentrated under reduced pressure The crude compound was purified by column chromatography

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: At 0° C., to a solution of 4-isopropylbenzoic acid (3.28 g, 20.0 mmol), triethylamine (2.12 g, 2.93 mL, 21.0 mmol) in dichloromethane/THF (15 mL/5 mL), is added isobutylchloroformate (2.87 g, 2.72 mL, 21.0 mmol). The mixture is stirred at 0° C. for 20 min. with warming to room temperature over 2 hr., and then treated with ethyl hydrazinoacetate (2.18 g, 21.0 mmol) and stirred overnight. The mixture is then washed with water, brine and dried over Na2SO4. The crude product obtained after the removal of the solvent is chromatographed (silica gel, 5:1 dichloromethane-ethyl acetate) to provide ethyl[2-(4-isopropylbenzoyl)hydrazino]acetate (4.85 g, 97%). MS (ES+): m/e 251. with warming to room temperature over 2 hr stirred overnight The mixture is then washed with water, brine dried over Na2SO4 The crude product obtained after the removal of the solvent is chromatographed (silica gel, 5:1 dichloromethane-ethyl acetate)

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

Procedure: (5-Formyl-3-phenyl-1,2,4-triazol-1-yl)-acetic acid ethyl ester, from Hydrazino-acetic acid ethyl ester and 2-Phenyl-oxazol-4-one. H-NMR: (CDCl3) δ 10.05 (s, 1H), 8.15 (d, 2H), 7.50 (m, 3H), 5.38 (s, 2H), 4.28 (m, 2H), 1.32 (t, 3H).

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

Procedure: A mixture of D16 (0.00138 mol), 2-hydrazinyl-acetic acid ethyl ester.monohydrochloride (1:1) (0.00276 mol) and K2CO3 (0.00206 mol) in t-BuOH (100 ml) was stirred at 85° C. overnight in a sealed reaction vessel. The reaction mixture was cooled, filtered and the filtrate's solvent evaporated in vacuo. Yield: 0.55 g of E10 (96.5%). The reaction mixture was cooled filtered the filtrate's solvent evaporated in vacuo

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of compound 44 (4 g, 14.0 mmol), ethyl 2-hydrazinylacetate (2.37 g, 15.0 mmol) and methanol (60 mL) was heated for 1.5 h. The reaction mixture was cooled to 0° C. and solvent was removed under reduced pressure. Water (100 mL) was added and the reaction mixture extracted with ethyl acetate (50 mL×3). Combined organic layer was washed with brine, dried over sodium sulphate and concentrated under reduced pressure. The crude compound was purified by column chromatography using 10% ethyl acetate in n-hexane as an eluent to afford the separated isomer 45 (1.2 g, 24%). was heated for 1.5 h solvent was removed under reduced pressure Water (100 mL) was added the reaction mixture extracted with ethyl acetate (50 mL×3) Combined organic layer was washed with brine dried over sodium sulphate concentrated under reduced pressure The crude compound was purified by column chromatography