NITROGEN-CONTAINING REMOTE FUNCTIONALIZED ORGANOLITHIUM COMPOUNDS BY REDUCTIVE OPENING OF 5-MEMBERED AND 6-MEMBERED HETEROCYCLES

The reaction of different five- or six-membered nitrogen-containing he terocycles such as N-isopropyl-2-phenylpyrrolidine (1), N-phenyl-3-pyr roline (6), N-phenylisoindoline (10), N-phenyltetrahydroisoquinoline ( 13) and N-methyltetrahydroisoquinoline (19) with an excess of lithium powder and a catalytic amount of DTBB (4.5 mol %), followed by treatme nt with electrophiles [H2O, D2O, MeI, CH2=CHCH2Br, (PrCHO)-C-i, Bu(t)C HO, PhCHO, Me(2)CO, Pr(n)COMe, PhCOMe, (CH2)(4)CO, (CH2)(5)CO, CO2] an d final hydrolysis gives a wide series of functionalised amines 3, 8, 9, 12 and 19, the key step in the process, being the reductive opening of the starting material giving a dianionic remote functionalised org anolithium compound. (C) 1996 Elsevier Science Ltd