Nitrogen → (5-(Methoxymethyl)thiophen-2-yl)methyl methanesulfonate

Participants

Reaction Conditions

Reaction Steps

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a solution of (5-(methoxymethyl)thiophen-2-yl)methanol (900 mg, 5.69 mmol) in dry CH2Cl2 (20.0 mL) was treated at 0° C. with Et3N (1.19 mL, 8.53 mmol) followed by DMAP (70 mg, 0.57 mmol) and Ms-Cl (0.57 mL, 7.39 mmol). After stirring at 0° C. for 1 h, the reaction was quenched with water (5 mL). The layers were separated and the aq. layer was extracted with CH2Cl2 (2×10 mL). The combined org. extracts were dried over MgSO4, filtered, and the solvents were removed under reduced pressure to give 1.38 of crude (5-(methoxymethyl)thiophen-2-yl)methyl methanesulfonate as an orange oil. LC-MS-conditions 07: tR=0.51 min. A solution of this crude material in DMF (10.0 mL) was added to a solution of 4-nitro-2H-[1,2,3]triazole (7.05 g of a 9.6% solution in DMF, 5.93 mmol) in DMF (15.0 mL) pre-treated for 30 min with DIPEA (1.96 mL, 11.9 mmol) and the reaction mixture was stirred overnight at 50° C. Water (10 mL), followed by EA (10 mL) was added. The aq. layer was extracted with EA (2×15 mL) and the combined org. extracts were washed with brine, dried over MgSO4, filtered, and the solvents were removed under reduced pressure. Purification of the residue by FC (gradient from 95:5 hept-EA to 80:20 hept-EA) gave the title compound as a yellow oil. TLC: rf (8:2 hept-EA)=0.36. LC-MS-conditions 07: tR=0.80 min.

Provenance & Evidence