The target product is synthesized from compound A in four steps. 1) Reaction with N,O-dimethylhydroxylamine hydrochloride, HATU, and DIEA gives intermediate 1. 2) Intermediate 1 reacts at low temperature with a Grignard reagent (prepared from magnesium and 2-bromopropene). Work-up yields intermediate 2. 3) Intermediate 2 reacts with benzonitrile in the presence of potassium carbonate and hydrogen peroxide at 0-4C to give intermediate 3. 4) Intermediate 3 is deprotected using trifluoroacetic acid. Work-up yields the final product. Specific molar ratios of reagents are required for each step.
