Ethyl propiolate → Ethyl 4,5,6,7-tetrahydropyrazolo[1,5-a]pyridine-2-carboxylate

HRID 2216565Notes

Reaction equation

HRID 2216565 reaction equation
[C:1]([O:5][CH2:6][CH3:7])(=[O:4])[C:2]#[CH:3].[NH:8]1[N:12]2[CH2:13][CH2:14][CH2:15][CH2:16][CH:11]2C(=O)O1>CC1C=CC=CC=1C>[CH2:6]([O:5][C:1]([C:2]1[CH:3]=[C:11]2[CH2:16][CH2:15][CH2:14][CH2:13][N:12]2[N:8]=1)=[O:4])[CH3:7]

Participants

4

Reactant 2

HCID 12182Ethyl propiolateHCID 69656246Tetrahydropyridino[1,2-c][1,2,3]oxadiazolone

Product 1

HCID 11845784Ethyl 4,5,6,7-tetrahydropyrazolo[1,5-a]pyridine-2-carboxylate

Reagents, catalysts & solvents 1

HCID 7237O-XyleneSolvent

Procedure

ethyl propiolate (804 mg) was added to the o-xylene (15 mL) solution of tetrahydropyridino[1,2-c][1,2,3]oxadiazolone (1.04 g) under a nitrogen atmosphere and refluxed for 16 h. The solution was concentrated under a reduced pressure. The residue was applied to silica gel column chromatography, then the column was eluted with n-hexane-AcOEt (2/1–1/1). The titled compound was obtained as yellow oil (871 mg, 65%), and 4,5,6,7-tetrahydropyrazolo[1,5-a]pyridine-3-carboxylic acid ethyl ester was obtained as yellow oil (345 mg, 26%).

Workup

  1. temperaturerefluxed for 16 h
  2. concentrationThe solution was concentrated under a reduced pressure
  3. washthe column was eluted with n-hexane-AcOEt (2/1–1/1)

Sources & evidence

ORD record
ord-29978c9488a343bb9ff571256cee99e6
Source dataset
uspto-grants-2006_09
Patent number
US07112582B2

Reaction notes

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