Triethylamine → 1-ethyl-5-pyrrolidin-1-yl-3-trimethylsilanylethynyl-1H-[1,2,4]triazole

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-bromo-1-ethyl-5-(pyrrolidin-1-yl)-1H-1,2,4-triazole (240 mg, 979 μmol, Eq: 1.00), ethynyltrimethylsilane (192 mg, 275 μl, 1.96 mmol, Eq: 2) and triethylamine (149 mg, 205 μl, 1.47 mmol, Eq: 1.5) in tetrahydrofuran (3.65 ml) was purged for 5 minutes with nitrogen. Then copper (I) iodide (1.86 mg, 9.79 μmol, Eq: 0.01), bis(triphenylphosphine)palladium(II) chloride (6.87 mg, 9.79 μmol, Eq: 0.01) and triphenylphosphine (2.57 mg, 9.79 μmol, Eq: 0.01) were added, the vessel was capped and heated to 120° C. for 1 day. Once more copper (I) iodide (1.86 mg, 9.79 μmol, Eq: 0.01), triphenylphosphine (2.57 mg, 9.79 μmol, Eq: 0.01), bis(triphenylphosphine)palladium(II) chloride (6.87 mg, 9.79 μmol, Eq: 0.01) and ethynyltrimethylsilane (192 mg, 275 μl, 1.96 mmol, Eq: 2) were added, the vial was purged with argon, capped again and stirred for one more day at 120° C. The crude material was applied on silica gel and purified by flash chromatography over a 20 g silica gel column using heptane/ethyl acetate 10-30% as eluent affording 1-ethyl-5-pyrrolidin-1-yl-3-trimethylsilanylethynyl-1H-[1,2,4]triazole (122 mg, 47.5%) as an orange oil. MS: m/z=263.4 (M+H+)

Provenance & Evidence