Acetic Acid → methyl [(4Z)-4-(1-ethoxypentylidene)-1-methyl-5-oxo-4,5-dihydro-1H-pyrazol-3-yl]acetate

HRID 1471441Notes

Reaction equation

ClC1C=CC=C[C:3]=1[N:8]1[C:12]([OH:13])=[CH:11][C:10]([CH2:14][C:15]([O:17][CH3:18])=[O:16])=[N:9]1.C(O)(=O)C.[CH2:23]([C:27](OCC)(OCC)[O:28][CH2:29][CH3:30])[CH2:24][CH2:25][CH3:26]>C(#N)C>[CH2:29]([O:28]/[C:27](=[C:11]1/[C:10]([CH2:14][C:15]([O:17][CH3:18])=[O:16])=[N:9][N:8]([CH3:3])[C:12]/1=[O:13])/[CH2:23][CH2:24][CH2:25][CH3:26])[CH3:30]

Participants

Conditions

Temperature: 70 °C

Procedure

The mixture of the above obtained methyl (5-hydroxy-1-methyl-1H-pyrazol-3-yl)acetate (Compound of Formula (IV), 0.80 g) in acetonitrile (5 mL), glacial acetic acid (21 μl, 0.1 equiv.) and BuC(OEt)3 (3 eq.) was heated at 70° C. for 1 h 15. The resulting red solution was concentrated in vacuo to afford a red syrup that was washed with cyclohexane and then dried in vacuo. Due to its relative instability, no further purification of methyl [(4Z)-4-(1-ethoxypentylidene)-1-methyl-5-oxo-4,5-dihydro-1H-pyrazol-3-yl]acetate was conducted (1.0 g, quantitative yield). MS (ESI+): 283.4; MS (ESI−): 281.3.

Workup

additionThe mixture of the
concentrationThe resulting red solution was concentrated in vacuo
customto afford a red syrup that
washwas washed with cyclohexane
customdried in vacuo
customDue to its relative instability, no further purification of methyl [(4Z)-4-(1-ethoxypentylidene)-1-methyl-5-oxo-4,5-dihydro-1H-pyrazol-3-yl]acetate

Sources & evidence

ORD record: ord-51df8a3a167c4b0aa05e10d430aac3e4
Source dataset: uspto-grants-2015_04
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09012449B2

Reaction notes

Loading…