Reaction equation
[CH2:1]1[O:11][C:4]2([CH2:9][CH2:8][C:7](=[O:10])[CH2:6][CH2:5]2)[O:3][CH2:2]1.C[Si]([N-][Si](C)(C)C)(C)C.[Li+].C([C:24]([O:26][CH2:27][CH3:28])=[O:25])#N.CCOC(C)=O>C1COCC1.O>[CH2:27]([O:26][C:24]([CH:8]1[C:7](=[O:10])[CH2:6][CH2:5][C:4]2([O:3][CH2:2][CH2:1][O:11]2)[CH2:9]1)=[O:25])[CH3:28]Participants
7
Conditions
- Temperature
- -78 °C
Procedure
1,4-Cyclohexanedione mono-ethylene ketal (25g) was dissolved in THF and cooled to −78° C. 1.0 M Lithium bis(trimethylsily)amide (160 mL) in THF was added dropwise. After 30 min, ethyl cyanoformate (15.9 mL) was added dropwise. After 60 min, the solution was poured into EtOAc and water containing ice. The organic layer was washed with water and brine before it was dried and concentrated. This crude was filtered through a plug of silica to give the 8-oxo-1,4-dioxa-spiro[4.5]decane-7-carboxylic acid ethyl ester (32.4 g). MS found: (M+H)+=228.9.
Workup
- waitAfter 60 min
- additioncontaining ice
- washThe organic layer was washed with water and brine before it
- customwas dried
- concentrationconcentrated
- filtrationThis crude was filtered through a plug of silica
Sources & evidence
- ORD record
- ord-a7e8a3e183f24cb7aa09137b6117fada
- Source dataset
- uspto-grants-2010_04
- Patent number
- US07696205B2
Linked notes
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