Synthetic applications of protected 2-aryl-4-piperidones. 7. Synthesis of 1-ethylindolo[2,3-a]quinolizidin-2-one
作者:Mario Rubiralta、Anna Diez、Cristina Vila、Yves Troin、Miguel Feliz
DOI:10.1021/jo00022a015
日期:1991.10
The synthesis of 1-ethylindolo[2,3-a]quinolizidin-2-one (1) by the intramolecular cyclization of protected N-(2-hydroxyethyl)-2-[1-(phenylsulfonyl)-3-indolyl]-4-piperidone 15 by the action of K(t)BuO and further acid treatment is reported. The methodology has been first carried out for its deethyl analogue 2 from (hydroxyethyl)piperidine 14 and has shown to be a good general method to reach indolo[2,3-a]quinolizidin-2-one systems. Compound 1 has also been obtained by an unusual rearrangement in acidic medium of 7-ethylhexahydropyrido[1',2':1,2]pyrazino[4,3-a]indole.