In the context of Tröger base chemistry, regio- and stereoselective C -H azidation reactions are reported. Azide functional groups are introduced at either one or the two benzylic positions selectively. Mild conditions and good yields are afforded by the combination of TMSN and iodosobenzene PhIO. The process occurs with high enantiospecificity (es 96-99 %) and-interestingly and importantly-via bridgehead iminium intermediates as shown by mechanistic and in-silico studies. Finally, mono- and bistriazole derivatives were prepared in high yields and enantiospecificity by using copper-catalyzed alkyne azide cycloaddition (CuAAC) reactions; some of the products were used as anion-binding organocatalysts for the tritylation of amines and alcohols.

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Density functional calculations are reported for complexes of general formula [(carbene)RhClL2] featuring model phosphino‐ and aminocarbenes. Both the cis and trans isomers of the rhodium(I) η1‐complexes (1–9) were investigated, and the influence of the rhodium co‐ligands (L=ethylene, phosphine, or carbon monoxide) was evaluated. In the case of phosphinocarbenes and carbon monoxide as a ligand, a somewhat unusual coordination mode was observed, in which a significant intramolecular Cl→Ccarbene interaction is present. The propensity of phosphino‐ and aminocarbenes to behave as four electron donors was also investigated both structurally and energetically on the related η2‐complexes 10–18. These results as a whole emphasize the structural versatility of phosphino‐ compared with aminocarbene complexes.

The cross enyne metathesis reaction of propargylic fluoride (+)-12 with ethylene affords the enantioenriched 1,3-diene (+)-14 having fluorine-containing side chain at 2-position in good yield. Upon Diels-Alder reaction, followed by aromatization, this diene affords the new benzylic fluorides (+)-16 and (+)-17 in high ee values. This new strategy has been successfully extended to the corresponding gem-difluoro diene 21 and benzylic fluorides 23 and 24.

A direct nitrene insertion into C-N bonds is observed upon treatment of methano-Tröger bases with arylsulfonyl iminophenyliodinanes under copper and dirhodium catalysis. Novel cyclic imino-methano Tröger bases are obtained (55-88%). Enantiopure products (ee ≥ 99%) can be obtained with tailored substrates.