Triethylamine → 1-Boc-4-(4-ethynylphenyl)piperazine

Participants

Reaction Conditions

Reaction Steps

A microwave vial was charged with tert-butyl 4-(4-iodophenyl)piperazine-1-carboxylate (300 mg, 0.773 mmol), trimethylsilylacetylene (0.22 mL, 1.54 mmol), NEt3 (3.0 mL), DMF (1.5 mL), CuI (15 mg, 0.080 mmol), and PdCl2 (PPh3)2 (27 mg, 0.039 mmol). The vial was capped and heated in the microwave at 100° C. for 1 h. After removing the NEt3 in vacuo, the residue was extracted with EtOAc (15 mL). The organic layer was then washed with NaHCO3 (sat.) (5 mL), H2O (5 mL), brine (5 mL) and then dried over MgSO4. The solvent was removed and then the material was dissolved into MeOH (4 mL) and THF (2 mL). K2CO3 (1.0 mL of a 1M solution) was added and the reaction stirred for 3 h. The solvent was removed and the residue extracted with EtOAc (15 mL). The organic layer was washed with brine (5 mL) and then dried over MgSO4. The solvent was removed and the product dried under high vacuum to give the title compound as a brown solid (212 mg, 96%); MS ESI 287.0 [M+H]+, calcd for [C17H22N2O2+H]+ 287.18.

Provenance & Evidence