350508-65-5Relevant academic research and scientific papers
Synthesis of enantiopure mono- and disubstituted tetrahydroisoquinolines by 6-exo radical cyclizations
Pedrosa, Rafael,Andrés, Celia,Iglesias, Jesús M,Obeso, Manuel A
, p. 4005 - 4014 (2007/10/03)
2-(o-Bromophenyl)-3-allyl- and 2-allyl-3-(o-bromobenzyl)-substituted perhydrobenzoxazines, derived from (-)-8-amino menthol, readily cyclized stereoselectively by reaction with tributyltin hydride in the presence of AIBN. The cyclization compounds were transformed into enantiopure 4-alkyl tetrahydroisoquinolines by reductive ring opening of the N,O-acetal moiety with lithium aluminum hydride. Enantiopure 1,4- and 3,4-dialkyl-substituted tetrahydroisoquinolines were also prepared by reaction of the cyclized compounds with methylmagnesium iodide and subsequent elimination of the menthol appendage.
