Malononitrile → Methyl 3,3-dicyano-2,2-dimethylpropanoate
Reaction equation
[H-].[Na+].[C:3](#[N:7])[CH2:4][C:5]#[N:6].Br[C:9]([CH3:15])([CH3:14])[C:10]([O:12][CH3:13])=[O:11].C(=O)([O-])O.[Na+]>C1COCC1>[C:5]([CH:4]([C:3]#[N:7])[C:9]([CH3:15])([CH3:14])[C:10]([O:12][CH3:13])=[O:11])#[N:6]Participants
Procedure
In THF (91 ml), 1.816 g (45.411 mmol) of sodium hydride (60% in mineral oil) were admixed gradually with 3 g (45.411 mmol) of malononitrile. Subsequently, 5.876 ml (45.411 mmol) of methyl 2-bromo-2-methylpropanoate were added and the mixture was stirred at room temperature overnight. Thereafter, another 5.876 ml (45.411 mmol) of methyl 2-bromo-2-methylpropanoate were added and the mixture was heated to 50° C. overnight. Then yet another 1.762 ml (13.623 mmol) of methyl 2-bromo-2-methylpropanoate were added and the mixture was heated to 50° C. for a further 4 h. The mixture was then admixed with saturated aqueous sodium hydrogencarbonate solution and extracted three times with ethyl acetate. The combined organic phases were washed with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered and concentrated to dryness. This gave 8.9 g of crude product, which was purified by chromatography on silica gel (4:1 cyclohexane-ethyl acetate).
Workup
- temperaturethe mixture was heated to 50° C. overnight
- temperaturethe mixture was heated to 50° C. for a further 4 h
- extractionextracted three times with ethyl acetate
- washThe combined organic phases were washed with saturated aqueous sodium chloride solution
- dry with materialdried over sodium sulfate
- filtrationfiltered
- concentrationconcentrated to dryness
- customThis gave 8.9 g of crude product, which was purified by chromatography on silica gel (4:1 cyclohexane-ethyl acetate)
Sources & evidence
- ORD record
- ord-2eaa685d0b0b4670a12b6a76fb0e88ed
- Source dataset
- uspto-grants-2014_07
- Patent number
- US08765769B2
Reaction notes
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