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The reaction rates of the water-trapping of unstable 1-norbornyl cations in relation to the rates of their rearrangement (ring contraction) have been experimentally determined. The activation barrier of the rearrangement reactions was calculated with the QST2 method, whereas the Marcus theory was applied to predict the activation barrier of the trapping reaction. All computations in gas phase were performed with the DFT B3LYP/6-31G(d) method, while the PCM model was used for the computation of unspecific solvent effects. The established methodology was able to predict the major product formed in the solvolysis of the corresponding triflate precursors of the studied carbocations. The agreement between experiment and theory supports, for the first time, the interesting conclusion that the very exergonic trapping-reaction of unstable 1-norbornyl cations takes place with relatively high barriers of activation and, hence, into the Marcus inverted region. Additionally, a noteworthy relationship between the free energy of activation for the carbocation rearrangement in gas phase and the length of the rearranging bond in the ground state is reported.

An empiric first approach to the knowledge about the structural factors influencing the catalytic behavior of conformationally flexible δ-amino-alcohol-based ligands, for the enantioselective addition of dialkylzincs to prochiral carbonyl groups, has been applied using the 1-(2-aminoethyl)norbornan-2-ol moiety as the model chiral system, and the asymmetrically catalyzed addition of diethylzinc to benzaldehyde as the test reaction. For this purpose, a selected small library of seven norbornane-based chiral ligands, bearing well-defined structural variations to allow a comparative study, that is, variation of the relative configuration and steric hindrance at the C(2), C(3) and/or C(7) norbornane positions, has been synthesized and probed in the mentioned test reaction. The experimental results obtained have been rationalized empirically using diastereomeric Noyori-like transition states, demonstrating that the conformational flexibility of the δ-amino-alcohol ligands, contrary to the more studied and rigid β-amino-alcohols, plays a crucial role on the catalytic behavior of such ligands (stereochemical sense and degree of the stereodifferentiation in the asymmetric process), which makes such structural factors, important for the improved design of new related chiral catalysts. In this sense, a robust crude empirical model for the prediction of the catalytic behavior of such δ-amino-alcohol-based ligands is proposed.

The competitive pathway timing for the previously described unexpected bromo-assisted Beckmann fragmentation of 7-anti-bromo-3,3-dimethyl-2-oxonorbornane-1-carboxamide has been investigated. It is concluded that this unusual process is activated by a synergic effect exerted by both the C(7)-anti-bromo and C(1)-aminocarbonyl groups. The effect consists in a specific intramolecular activation of the bromo-assistance by the bridgehead aminocarbonyl group.

The mechanism of the Leuckart reaction of 3,3- and 7,7-dimethyl-2-oxo-1-norbornyl triflates and triflamides, synthesised by us starting from (1R)-camphor and (1R)-fenchone, has been studied. Strikingly, the electron-withdrawing capacity of the bridgehead substituents has demonstrated not to be enough to control the Wagner–Meerwein rearrangement during the course of the reaction, so that only both enantiomers of a 3,3-dimethylnorbornanediamine derivative have been obtained as final products. As a result, the total synthesis of these interesting chiral compounds has been optimised and shortened until three overall steps starting from (1R)-fenchone.

The reaction of different substituted 2-norbornanones 1 with triflic anhydride in the presence of nitriles 6 is carried out in order to study the factors that influence on the different reaction possibilities of 2-norbornyl carbocations. The syntheses of interesting annulated pyrimidine derivatives 10 and conformationally rigid 1,3 disubstituted products are described.

A general and straightforward enantiospecific access to synthetically valuable 10-N-substituted camphors (amines and secondary amides) has been developed. The synthetic method uses camphor as the starting enantiopure material and takes place in five individual steps with a high overall yield. The process involves a stereocontrolled double-Wagner–Meerwein-rearrangement strategy to generate key-intermediate 10-(triflyloxy)camphor, a peculiar and highly-reactive primary triflate, which is able to alkylate soft N-nucleophiles, such as amines and nitriles, easily and without producing Grob-like fragmentation of the β-(triflyloxy)ketone-based norbornane system.

The solvolysis of 3,3-dimethyl-2-oxo- and 2,2-dimethyl-3-oxo-1-norbornyl triflates (6 and 8) takes place with formation of ring contracted and fragmented products respectively. The effect of the substituents on the solvolysis rates is explained taking into account n- and σ-participation. This n,σ-participation causes changes in the structure and stability of the intermediate carbocations, which can be detected by the AM1 method.