Carbon tetrabromide → 5'-Azido-2',5'-dideoxy-5-(2-chloroethyl)uridine

Participants

Reaction Steps

1.4 g of 5-(2-chloroethyl)-2'-deoxyuridine and 1.3 g of triphenylphosphine were dissolved in 20 ml of dimethylformamide and stirred while 1.2 g of lithium azide were added to give a solution within 5 minutes at room temperature. 1.7 g of carbon tetrabromide were added portionwise during 5 minutes to give a hazy orange colored solution which was stirred at room temperature for 17 hours. 5 ml of methanol were added to give a clear solution. After 0.5 hour, the solvents were removed by evaporation under an oil pump vacuum to give a gum which was partitioned between 30 ml of ethyl acetate and 20 ml of water. The white solid which formed was removed by filtration to give 0.64 g of crude product of melting point 179°-182° C. (decomposition). This crude product was stirred with methanol and then removed by filtration to give 0.48 g of pure 5'-azido-2',5'-dideoxy- 5-(2-chloroethyl)-uridine of melting point 197°-199° C. (decomposition).

Provenance & Evidence