Sodium Bicarbonate → (R)-5-(5-bromo-2-fluorophenyl)-6,6-difluoro-5,7,7-trimethyl-1,4-oxazepan-3-one

Participants

Reaction Conditions

Reaction Steps

To a solution of (R)-ethyl 2-(4-amino-4-(5-bromo-2-fluorophenyl)-3,3-difluoro-2-methylpentan-2-yloxy)acetate (intermediate A27A) (6.85 g, 16.6 mmol) in toluene (205 ml) at 23° C. was dropwise added trimethylaluminum (2 M in toluene, 10.8 ml, 21.6 mmol) and the light yellow solution was stirred at 23° C. for 2 h. Poured into sat. NaHCO3-sol., extracted with ethyl acetate, washed organic layer with brine, dried over Na2SO4, filtered off and evaporated totally, dried in high vacuum to give the (R)-5-(5-bromo-2-fluorophenyl)-6,6-difluoro-5,7,7-trimethyl-1,4-oxazepan-3-one (5.95 g, 16.2 mmol, 97.8% yield) as a light yellow solid, which was used without further purification. MS (ISP): m/z=366.2 [(M+H)+] and 368.1 [(M+2+H)+].

Provenance & Evidence