1,2-Dibromoethane → HCID 86590140, compound

Participants

Reaction Conditions

Reaction Steps

A suspension of 6 g (92 mmol) of zinc powder and 0.4 ml (4.7 mmol) of 1,2-dibromoethane in 7 ml of anhydrous N,N-dimethylformamide is heated at 60° C. with stirring and under argon for 45 min. 0.126 ml (1 mmol) of trimethylsilyl chloride is then added and the mixture is stirred vigorously at room temperature for 30 min. A solution of 7 g (15.4 mmol) of phenylmethyl (S)-4-iodo-2-[[(phenylmethoxy)carbonyl]amino]butanoate in 1 ml of anhydrous N,N-dimethylformamide is then added. After 30 min at room temperature, 0.28 g (0.31 mmol) of tris(dibenzylideneacetone)dipalladium (0), 0.38 g (1.24 mmol) of tri-ortho-tolylphosphine, 3.78 g (18.5 mmol) of 2-bromo-5-nitropyridine and 1 ml of anhydrous N,N-dimethylformamide are added at room temperature and the mixture is stirred for 3 h at room temperature. The reaction medium is taken up in 200 ml of ethyl acetate and 5 g of active charcoal and then filtered through a cake of Celite. The cake is rinsed with 2×100 ml of ethyl acetate and the organic phases are combined, washed with 5×100 ml of water, dried over sodium sulphate and concentrated under reduced pressure. The residue is purified by filtration on a column of silica gel, eluting with a cyclohexane/ethyl acetate gradient of from 0 to 20% ethyl acetate. 5.16 g of phenylmethyl (S)-5-nitro-α-[[(phenylmethoxy)carbonyl]amino]-2-pyridinebutanoate are thus obtained in the form of a yellow foam.

Provenance & Evidence