Tertiary amines with very high steric congestion

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Sterically hindered amines play an important part in organic synthesis, for example, as bases with low nucleophilicity. They are utilized to prepare a variety of other products, for instance, spin-label compounds. The application of sterically hindered amines as light stabilizers in polymeric materials is also quantitatively of great importance. In basic research, special features of structures, such as the degree of flattening in the pyramidal structure of triisopropylamine, were intensively investigated and controversially discussed. Simple trialkylamines with significantly higher steric hindrance, for example, tri-tert-butylamine, are unknown and should be prepared within the project via nine different methods of synthesis for the first time. The novel products have to be analyzed in view of the packing and molecular structures in single crystals and in connection with conformational equilibria in solution (dynamic NMR spectroscopy and 15N NMR). We assume that the steric congestion in these tertiary amines has been underestimated up to now. Therefore, an unexpectedly high reactivity, for instance, in the easily occurring cleavage into a secondary amine and an alkene, will be the consequence.