An Approach to the Synthesis of 2-Methyl-triclisine, an Unnatural Analog of Triclisine, Employing a Microwave-Assisted Electrocyclization

SILVEIRA, CLAUDIO C.; LARGHI ENRIQUE L; MENDES, SAMUEL R.; BRACCA, ANDREA B. J.; RINALDI, FRANCIELI; KAUFMAN, TEODORO S.

Sao Pedro (SP) Brasil

Otro; 13th Brazilian Meeting on Organic Synthesis (BMOS); 2009

Sociedade Brasileira de Quimica

The synthesis of 2-methyltriclisine, an unnatural analog of the azafluoranthene alkaloid triclisine, is reported. The synthesis was achieved in 10 steps and 21% overall yield from 2-bromo-4-dimethoxybenzaldehyde, through the intermediacy of 3,4-dimethoxyfluoren-9-one. Construction of the heterocyclic ring entailed the para-Claisen rearrangement ofan allyl-4-fluorenyl ether, followed by isomerization of the resulting 2-allylfluoren-9-one and a microwave-assisted electrocyclization of the aza (6-phi)-electron system formed by oximation of its carbonyl function.