Benzyl Bromide → 2-Phenylmethyl-4-propyl-1,2,5-thiadiazolidin-3-one 1,1-dioxide

Participants

Reaction Steps

Eight grams (44.94 mmol) of 4-isopropyl-1,2,5-thiadiazolidin-3-one 1,1-dioxide (which was dissolved in methanol, brought to pH 5 with ion exchange resin, filtered, and concentrated in vacuo to remove methanol), phenylmethyl bromide (8.09 g, 47.2 mmol), and tetrabutylammonium bromide (1.5 g, 4.66 mmol) suspended in toluene/DMF (200 ml/50 ml) was allowed to react at 130° C. for 30 hours. The resulting mixture was cooled, the excess toluene was concentrated in vacuo, and the residue was diluted with 200 ml of water and extracted with ether/ethyl acetate (4:1, 700 ml). The organic layer was washed with water and brine, dried and concentrated in vacuo to yield a residue which was purified by flash chromatography to afford 8.6 g (72%) of 2-phenylmethyl-4-isopropyl-1,2,5-thiadiazol-idin-3-one 1,1-dioxide (Formula IX: R1 =H; R2 =isopropyl) as a solid.

Provenance & Evidence