N-(tert-butoxycarbonyl)glycine → N-t-butoxycarbonylglycine iodopropargyl ester

Participants

Reaction Conditions

Reaction Steps

To a magnetically stirred solution of N-t-butoxycarbonylglycine (3.00 g., 17.12 mmole) and iodopropargyl alcohol (3.12 g., 17.15 mmole) in anhydrous dichloromethane (40 ml.) cooled to 0° C. with an ice-bath was added 4-dimethylaminopyridine (0.21 g., 1.72 mmole) followed by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (3.61 g., 18.83 mmole). After stirring at 0° C. for 1/2 hour, the reaction mixture was stored in a refrigerator at 6° C. overnight. The reaction mixture was transferred to a separatory funnel and diluted to 100 ml. with dichloromethane, then washed successively with water, 10% aqueous potassium hydrogen sulfate, water, saturated aqueous sodium bicarbonate, water and a final wash with saturated aqueous sodium chloride. The organic layer was dried with magnesium sulfate, filtered and concentrated in vacuo with a rotary evaporator to a clear colorless oil which crystallized on standing as N-t-butoxycarbonylglycine iodopropargyl ester (5.60 g., 96.4% yield). m.p.=65°-68° C. 1H-NMR (200 MHz, DMSOd6)δ=1.40 ppm, s, 9H; 3.73, d, 2H; 4.86, s, 2H; 7.28, t, 1H. IR (CDCl3) 1165, 1505, 1715, 1760, 2205, 3460 cm-1.

Provenance & Evidence