[O:1]=[C:2]1[C:6]2([CH2:11][CH2:10][CH2:9][N:8]([C:12]([O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:13])[CH2:7]2)[CH:5]([C:19]2[CH:24]=[CH:23][C:22]([CH3:25])=[CH:21][CH:20]=2)[CH2:4][NH:3]1.[Li+].[CH3:27][Si]([N-][Si](C)(C)C)(C)C.IC.[Cl-].[NH4+]>C1COCC1>[CH3:27][N:3]1[CH2:4][CH:5]([C:19]2[CH:20]=[CH:21][C:22]([CH3:25])=[CH:23][CH:24]=2)[C:6]2([CH2:11][CH2:10][CH2:9][N:8]([C:12]([O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:13])[CH2:7]2)[C:2]1=[O:1]To a stirred solution of tert-butyl 1-oxo-4-p-tolyl-2,7-diazaspiro[4.5]decane-7-carboxylate (333 mg, 0.967 mmol) in dry THF (6 ml) at −60° C. under nitrogen was added LiHMDS 1M in THF (1.26 ml, 1.257 mmol) dropwise and the mixture was left to stir at −60° C. for 1 hr. After this time a solution of iodomethane (79 ul, 1.257 mmol) in dry THF (1 ml) was added dropwise at −60° C. and the reaction mixture was allowed to warm from −60° C. to room temperature over 1 hr. After a further 3 hrs at room temperature the reaction mixture was added to sat. ammonium chloride (25 ml), extracted with EtOAc (3×25 ml) and the combined organics were washed with brine (25 ml), dried (MgSO4) and concentrated under reduced pressure to give the crude product as an orange oil. The crude material was purified via silica chromatography eluting with 20-80% iso-hexane/EtOAc. The appropriate fractions were combined and concentrated to give the product as a yellow solid (270 mg).
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