Scheme 11.

Proposed mechanism for the formation of the main cyclic products 45⁻ and 46⁻ via low temperature reaction of bromoethyl or bromopropyl phthalimide with lithiated Cs1 and the schematic images of molecular structures of the compounds determined by XRD and presented in ref. [79], cations and solvent atoms are omitted for clarity. Boron atomsare drawn in green, carbon in gray, cobalt in rose, nitrogen in blue, and oxygen in red color.