Acetic Acid → 1-[(2-t-Butyldimethylsilyloxyethoxy)methyl]-5-ethyl-6-phenylthio-2-thiouracil

Participants

Reaction Conditions

Reaction Steps

Next, 11 ml (22 mmol) of 2.0M solution of lithium diisopropylamide in tetrahydrofuran was added under a nitrogen atmosphere to 30 ml of tetrahydrofuran which has been cooled down to -70° C. in advance. To this was added dropwise 14 ml of tetrahydrofuran solution containing 3.4 g (10 mmol) of the thus obtained 1-[(2-t-butyldimethylsilyloxyethoxy)methyl]-5-ethyl-2-thiouracil by keeping the reaction solution at a temperature of -70° C. or lower. The resulting mixture was stirred for 1 hour at -70° C. To this was added dropwise 10 ml of tetrahydrofuran solution containing 2.8 g (13 mmol) of diphenyl disulfide. After 1 hour, the resulting reaction mixture was further mixed with 1.3 ml of acetic acid, adjusted to room temperature and subjected to partition using an ethyl acetate-water system, and then the organic layer was evaporated to dryness. Thereafter, the residue was adsorbed on a silica gel column and eluted with chloroform to obtain 3.4 g (76%) of 1-[(2-t-butyldimethylsilyloxyethoxy)methyl]-5-ethyl-6-phenylthio-2-thiouracil.

Provenance & Evidence