Reaction equation
[CH2:1]([O:3][CH:4]([O:7][CH2:8][CH3:9])[C:5]#[CH:6])[CH3:2].[Li]CCCC.CON(C)[C:18](=[O:28])[C:19]1[CH:24]=[CH:23][C:22]([N+:25]([O-:27])=[O:26])=[CH:21][CH:20]=1.Cl>C1COCC1>[CH2:1]([O:3][CH:4]([O:7][CH2:8][CH3:9])[C:5]#[C:6][C:18]([C:19]1[CH:20]=[CH:21][C:22]([N+:25]([O-:27])=[O:26])=[CH:23][CH:24]=1)=[O:28])[CH3:2]Participants
Conditions
- Temperature
- -70 °C
Procedure
3,3-Diethoxyprop-1-yne (8.5 ml, 59 mmol) was dissolved in THF (100 ml). The solution was cooled to −70° C., and nBuLi (19 ml of 2.5 M soln in hexanes, 47.5 mmol) was added over 5 min. The solution was warmed to 0° C. for 15 min, then cooled to −70 ° C. again. A solution of N-methoxy-N-methyl-4-nitrobenzamide (Intermediate 8, 8.04 g, 38.1 mmol) in THF (50 ml) was added dropwise over 15 min. The solution was warmed to 0° C. after 15 min, and held there for 45 min. The reaction mixture was poured into 1M HCl, extracted with ethyl acetate and dried over sodium sulfate. Purification by chromatography on silica gel eluting with 30 to 50% dichloromethane: hexane, gave the title compound as a light orange oil which solidified on standing (7.14 g).
Workup
- temperatureThe solution was warmed to 0° C. for 15 min
- temperaturecooled to −70 ° C. again
- temperatureThe solution was warmed to 0° C. after 15 min
- extractionextracted with ethyl acetate
- dry with materialdried over sodium sulfate
- customPurification by chromatography on silica gel eluting with 30 to 50% dichloromethane
Sources & evidence
- ORD record
- ord-52ad3e59f4f24aa3a7736f9b578531f6
- Source dataset
- uspto-grants-2007_03
- Patent number
- US07186738B2
Linked notes
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