Triphenylphosphine → tert-Butyl [2-(6-acetyl-2-bromo-4-chloro-3-methylphenoxy)ethyl]carbamate

Participants

Reaction Conditions

Reaction Steps

A suspension of 1-(3-bromo-5-chloro-2-hydroxy-4-methylphenyl)ethanone (8.0 g, 30 mmol) in methylene chloride (304 mL) was heated with a heat gun to dissolve the solids and cooled to 0° C. To the mixture was added triphenylphosphine (11 g, 43 mmol) and tert-butyl (2-hydroxyethyl)carbamate (9.4 mL, 61 mmol). Diisopropyl azodicarboxylate (8.4 mL, 43 mmol) was added dropwise. The mixture was stirred for 23 hours at room temperature. The reaction mixture was poured into water and extracted with methylene chloride. The organic layer was separated, washed with brine, dried with sodium sulfate, filtered, and concentrated. The oil was dissolved in methylene chloride and was purified on silica using ethyl acetate in hexanes (0-25%) to give the desired compound (7.3 g, 59%). LCMS calculated for C16H21BrClNO4Na (M+Na)+: m/z=428.0, 430.0; found: 428.0, 430.0.

Provenance & Evidence