Far Away from Flatland. Synthesis and Molecular Structure of Dihetera[3.3.]propellanes and Trihetera[3.3.]propellanes: Advanced Analogues of Morpholine/Piperazine.

An approach to di- and trihetera[3.3.]propellanes ( = 2-4 ), advanced morpholine and piperazine analogues, is developed.

Scalable Synthesis of Biologically Relevant Spirocyclic Pyrrolidines.

Synthetic approaches toward multigram preparation of spirocyclic α,α-disubstituted pyrrolidines from readily available starting materials are discussed. It was shown that although a number of synthetic methodologies have been known to date, many of the title compounds remain hardly accessible. The most appropriate literature method (which relied on reaction of imines and allyl magnesium halide, followed by bromocyclization) was identified and optimized.