Phosphonium, (2-methoxy-2-oxoethyl)triphenyl-, bromide (1:1) → methyl (E)-3-[3-bromo-5-(1-cyanocyclopropyl)phenyl]prop-2-enoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a suspension of (2-methoxy-2-oxo-ethyl)-triphenyl-phosphonium bromide (1.502 g, 3.618 mmol) in THF (15 mL) under nitrogen at room temperature was added LHMDS in THF (3.358 mL of 1 M, 3.358 mmol) dropwise. The mixture was stirred for 10 mins then cooled to −25° C. 1-(3-bromo-5-formyl-phenyl)cyclopropane-1-carbonitrile (500 mg, 1.999 mmol) was dissolved in 1 mL of THF and added to the reaction. The reaction was allowed to warm to room temperature over 1 hour. The reaction was quenched with MeOH (2 mL) and then partitioned between ethyl acetate and brine. The aqueous was extracted with ethyl acetate and dried, filtered and concentrated. The crude product was purified on silica (Companion, 24 g) eluting with 1-20% EtOAc:Petrol ether to give methyl (E)-3-[3-bromo-5-(1-cyanocyclopropyl)phenyl]prop-2-enoate as a yellow solid (594 mg, 97%).

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