An efficient strategy for the construction of X-azatricyclo[m.n.0.0 a,b]alkanes by intramolecular [3 +2] cycloaddition of nonstabilized cyclic azomethine ylides

Abstract

Various new structural entities related to X-azatricyclo[m.n.0.0. a,b]alkanes 15a-d are constructed employing the intramolecular [3+2]-dipolar cycloaddition of nonstabilized cyclic azomethine ylides. The ylides are generated by the sequential double desilylation of N-alkyl-α,α′-bis(trimethylsilyl)cyclic amines 14a-d using Ag(I)F as a one-electron oxidant. More rigid azatetracyclo compounds of type 23, in which benzene ring is attached as a tether unit in the N-alkyl chain moiety, are also synthesized by the cyclization of 22. These rigid azatricyclo compounds 15 and 23 possess structural resemblance to the rigid azatricyclo analogues 8-10, which are reported to exhibit selective and high binding affinity at dopamine transporter (DAT).