Lithium Hexamethyldisilazide → HCID 86730036, compound

Participants

Reaction Conditions

Reaction Steps

To a mixture of (5R,7S)-7-(4-bromophenyl)-3-oxa-1-azaspiro[4.4]nonan-2-one (I-3, 1 g, 3.38 mmol) in dioxane (10 mL) at room temperature was added lithium bis(trimethylsilyl)amide (3.71 mL, 3.71 mmol). The mixture was stirred for 30 minutes, then 1,2,3,4,5-pentaphenyl-1′-(di-t-butylphosphino)ferrocene (0.121 g, 0.169 mmol), Pd2(dba)3 (0.155 g, 0.169 mmol) and (2-(tert-butoxy)-2-oxoethyl)zinc(II) chloride (8.10 mL, 4.05 mmol) were added. The reaction mixture was heated at 80° C. for 2 hours, then cooled to room temperature, diluted with ethyl acetate and washed with 1M HCl. The organic layer was dried with MgSO4, filtered and concentrated. The crude material was purified on a silica gel cartridge (40 g) using an EtOAc/hexane gradient (0-100% EtOAc over 20 minutes) to afford 950 mg of tert-butyl 2-(4-((5R,7S)-2-oxo-3-oxa-1-azaspiro[4.4]nonan-7-yl)phenyl)acetate. HPLC retention time=0.93 min (Condition G); LC/MS M+1=332.

Provenance & Evidence