Microwave-assisted Michael-type addition of 1-(arylsulfonyl)-pyrroles and -indoles to methyl vinyl ketone using bismuth triflate as catalyst

The Michael type addition of pyrroles and indoles bearing strongly electron-withdrawing N-protecting groups (e.g., arylsulfonyl-, benzoyl-) to methyl vinyl ketone have not been previously reported. We find that such alkylative processes can be effected in low to moderate yields using bismuth triflate as catalyst in conjunction with microwave irradiation. [GRAPHICS] .