4-Toluenesulfonyl chloride → HCID 91462899, compound

Participants

Reaction Steps

To a mixture of 2.2.c (R=Me, P=TBDMS, A=COOCH3) (279 mg, 0.828 mmol), p-toluenesulfonyl chloride (323 mg, 1.69 mmol, 98%), DMAP (5.1 mg, 0.042 mmol) in 10 ml of dry CH2Cl2 at 0° C. (ice bath) was added Et3N (308 μL, 2.54 mmol). The mixture was refluxed for three days; then p-toluenesulfonyl chloride (320 mg, 1.69 mmol, 98%), DMAP (5.1 mg, 0.042 mmol) and Et3N (500 μL) were added. The resulting solution was refluxed for two days, p-toluenesulfonyl chloride (320 mg, 1.69 mmol, 98%), DMAP (5.1 mg, 0.042 mmol) and Et3N (500 μL) were added again and reflux was continued for another day. The resulting mixture was diluted with 20 ml of CH2Cl2, washed with brine and the aqueous phase was extracted with EtOAc (4×50 ml). The combined organic phases were dried over MgSO4. Filtration of the solvent, concentration and flash chromatography on silica (isooctane/EtOAc: 9:1), afforded 2.3.c (R=Me, P=TBDPS, L=OTos, A=COOCH3) (316 mg, 83.5%) as a light yellow oil.

Provenance & Evidence