Dichloromethane → 3-Methoxy-2-methylbenzohydrazide
Reaction equation
[C:1]([O-:4])([O-])=O.[K+].[K+].[OH2:7].[NH2:8][NH2:9].CO[C:12]1[CH:13]=[C:14]([CH:18]=[CH:19][CH:20]=1)[C:15](Cl)=O.[CH2:21](Cl)Cl>O.C(Cl)(Cl)Cl>[CH3:21][O:7][C:13]1[C:14]([CH3:15])=[C:18]([CH:19]=[CH:20][CH:12]=1)[C:1]([NH:8][NH2:9])=[O:4]Participants
Procedure
To a 500 mL, 3-neck flask equipped with magnetic stirring, and chilled in an ice water bath, were added 50 mL CH2Cl2, followed by a solution of 32 g (231 mmol) K2CO3 dissolved in 80 mL water, and 24 g (479 mmol) hydrazine hydrate. Over a period of 30-60 minutes, a solution of 20 g (108.3 mmol) 2-methyl, 3-methoxybenzoyl chloride dissolved in 100 mL CH2Cl2 were added, while keeping the temperature below 10° C. The reaction mixture was stirred for an additional hour, during which time a precipitate formed. The precipitate was collected and shaken with a CH2Cl2/CHCl3 mixture; the liquid phase was separated from remaining solids, and solvent was removed in vacuo to leave 5.85 g crude product hydrazide. Meanwhile, the original CH2Cl2 solution was transferred to a separatory funnel, diluted with CHCl3, and shaken with water. The organic layer was removed, washed again with water, dried, and solvent was evaporated to leave a solid residue. This was washed thoroughly with hexane and filtered to provide an additional 6.05 g crude product hydrazide. The combined crude hydrazide was recrystallized from hot ether or ethyl acetate/hexane mixtures to yield 10.04 g 3-methoxy-2-methyl-benzoic acid hydrazide: 1H NMR (300 MHz, CDCl3) δ (ppm): 7.2 (t, 1H), 6.95 (br s, 1H), 6.9 (m, 2H), 4.15 (br s, 2H), 3.84 (s, 3H), 2.27 (s, 3H).
Workup
- customTo a 500 mL, 3-neck flask equipped with magnetic stirring
- temperaturechilled in an ice water bath
- additionwere added
- customthe temperature below 10° C
- customformed
- customThe precipitate was collected
- stirringshaken with a CH2Cl2/CHCl3 mixture
- customthe liquid phase was separated
- customwas removed in vacuo
- customto leave 5.85 g crude product hydrazide
- customThe organic layer was removed
- washwashed again with water
- customdried
- customsolvent was evaporated
- customto leave a solid residue
- washThis was washed thoroughly with hexane
- filtrationfiltered
- customto provide an additional 6.05 g crude product hydrazide
- customwas recrystallized from hot ether or ethyl acetate/hexane
Sources & evidence
- ORD record
- ord-795c44fd177a43e4ab6a9954c62a8344
- Source dataset
- uspto-grants-2014_06
- Patent number
- US08748125B2
Reaction notes
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