No abstract

Indoles are converted into α-carbolines in four steps by acylation at C-3, Boc-protection, olefination of the resulting 3-indolyl aldehydes or ketones to give N-Boc-3-indolyl alkenyl oxime O-methyl ethers, which upon heating to 240 °C under microwave irradiation undergo loss of the Boc-group, and 6π-electrocyclization to α-carbolines, following aromatization by loss of methanol (11 examples, 30–90% yield).

Olefination of 3‐indolyl aldehydes or ketones provide indole‐3‐alkenyl oximes, which upon microwave heating undergo Boc‐deprotection, 6π‐electrocyclization, and aromatization to form α‐carbolines.