Benzyl chloroformate → (R)-2-(((Benzyloxy)carbonyl)amino)pent-4-enoic acid

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Reaction Steps

A mixture of D-allylglycine (2.8 g, 24.3 mmol), 1M aqueous sodium hydroxide solution (25 ml), and tetrahydrofuran (10 ml, distilled from ketyl) was stirred at room temperature until homogeneous then cooled in an ice-bath. To the resulting rapidly stirred solution was added about 5 mL of 1.0M aqueous sodium hydroxide solution then dropwise about 1 g of benzyl chloroformate. This was repeated 4 additional times until a total of 28 mL of 1.0M aqueous sodium hydroxide soltuion and 4.80 g (95%, 27 mmol) of benzyl chloroformate were added. The reaction mixture was stirred for 15 minutes at 0° C. then 30 minutes at room temperature and then extracted with 50 mL of ether. The aqueous layer was acidified (pH=1.5) the by addition of 6N hydrochloric acid solution (about 10 mL) then extracted with three-50 mL portions of ether. The three ether extracts were combined, dried (magnesium sulfate) and concentrated in vacuo to afford 6.01 g of title product as a colorless oil.

Provenance & Evidence