pent-2-ynoic acid

Conditions: temp:-10.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Pentynoic acid (200 mg, 2.04 mmol) was dissolved in THF (4 mL). The solution was cooled in a brine-icewater bath. A solution of dicyclohexylcarbodiimide (421 mg, 2.04 mmol) in THF (2 mL) was added. 3-Hydroxy-1,2,3-benzotriazin-4(3H)-one (333 mg, 2.04 mmol) was added after 5 minutes. The reaction mixture was stirred 1 h at −10° C. and then 2 h at room temperature. TLC indicated full conversion of 3-hydroxy-1,2,3-benzotriazin-4(3H)-one (eluent: ethyl acetate). Precipitated salts were filtered off. The filtrate was concentrated in vacuo and crystallized from hexane (4 mL). The crystals were filtered off and dried. Yield: 450 mg, 93%. RF=0.8 (ethyl acetate). The solution was cooled in a brine-icewater bath 2 h at room temperature Precipitated salts were filtered off The filtrate was concentrated in vacuo crystallized from hexane (4 mL) The crystals were filtered off dried

Conditions: temp:-10.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Pentynoic acid (200 mg, 2.04 mmol) was dissolved in THF (4 mL). The solution was cooled in a brine-icewater bath. A solution of dicyclohexylcarbodiimide (421 mg, 2.04 mmol) in THF (2 mL) was added. 3-Hydroxy-1,2,3-benzotriazin-4(3H)-one (333 mg, 2.04 mmol) was added after 5 minutes. The reaction mixture was stirred 1 h at −10° C. and then 2 h at room temperature. TLC indicated full conversion of 3-hydroxy-1,2,3-benzotriazin-4(3H)-one (eluent: ethyl acetate). Precipitated salts were filtered off. The filtrate was concentrated in vacuo and crystallized from hexane (4 mL). The crystals were filtered off and dried. Yield: 450 mg, 93%. RF=0.8 (ethyl acetate). The solution was cooled in a brine-icewater bath 2 h at room temperature Precipitated salts were filtered off The filtrate was concentrated in vacuo crystallized from hexane (4 mL) The crystals were filtered off dried

Conditions: temp:-10.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Pentynoic acid (200 mg, 2.04 mmol) was dissolved in THF (4 mL). The solution was cooled in a brine-icewater bath. A solution of dicyclohexylcarbodiimide (421 mg, 2.04 mmol) in THF (2 mL) was added. 3-Hydroxy-1,2,3-benzotriazin-4(3H)-one (333 mg, 2.04 mmol) was added after 5 minutes. The reaction mixture was stirred 1 h at −10° C. and then 2 h at room temperature. TLC indicated full conversion of 3-hydroxy-1,2,3-benzotriazin-4(3H)-one (eluent: ethyl acetate). Precipitated salts were filtered off. The filtrate was concentrated in vacuo and crystallized from hexane (4 mL). The crystals were filtered off and dried. Yield: 450 mg, 93%. RF=0.8 (ethyl acetate). The solution was cooled in a brine-icewater bath 2 h at room temperature Precipitated salts were filtered off The filtrate was concentrated in vacuo crystallized from hexane (4 mL) The crystals were filtered off dried

Conditions: temp:-10.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Pentynoic acid (200 mg, 2.04 mmol) was dissolved in THF (4 mL). The solution was cooled in a brine-icewater bath. A solution of dicyclohexylcarbodiimide (421 mg, 2.04 mmol) in THF (2 mL) was added. 3-Hydroxy-1,2,3-benzotriazin-4(3H)-one (333 mg, 2.04 mmol) was added after 5 minutes. The reaction mixture was stirred 1 h at −10° C. and then 2 h at room temperature. TLC indicated full conversion of 3-hydroxy-1,2,3-benzotriazin-4(3H)-one (eluent: ethyl acetate). Precipitated salts were filtered off. The filtrate was concentrated in vacuo and crystallized from hexane (4 mL). The crystals were filtered off and dried. Yield: 450 mg, 93%. RF=0.8 (ethyl acetate). The solution was cooled in a brine-icewater bath 2 h at room temperature Precipitated salts were filtered off The filtrate was concentrated in vacuo crystallized from hexane (4 mL) The crystals were filtered off dried