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Abstract (summary): New main group systems that provide avenues for small molecule activation have been illustrated using frustrated Lewis pairs (FLPs) – combinations of sterically encumbered Lewis acids and bases which cannot form adducts. The research presented herein expands the small molecule activation and transformation of FLPs using B(C6F5)3. Combination of the aryl amine tBuNHPh and B(C6F5)3 under H2 at room temperature leads to its heterolytic splitting forming the complex [tBuNH2Ph][HB(C6F5)3]. Exposing the salt to elevated temperatures is found to follow an alternative mechanism resulting in hydrogenation of the N-bound phenyl ring affording the isolable cyclohexylammonium salt [tBuNH2Cy][HB(C6F5)3]. This finding is extended to include a series of N-phenyl amines, in addition to mono- and di-substituted pyridines, quinolines and several other N-heterocycles. The reaction of B(C6F5)3 and H2 with other substrates, namely ketones and aldehydes are also investigated. Catalytic hydrogenation of the carbonyl functional group is achieved in an ethereal solvent to give alcohol products. In these cases, the borane and ether behave as a FLP to activate H2 and effect the reduction. Similar reductions are also achieved in toluene using B(C6F5)3 in combination with cyclodextrins or molecular sieves. Reductive deoxygenation occurs in the particular case of aryl ketones. Finally, the Lewis acid B(C6F5)3 is found to enable the intermolecular hydroamination of various terminal alkynes giving iminium alkynylborate complexes of the general formula [RPhN=C(CH3)R1][R1C≡CB(C6F5)3]. The three-component reaction can also be performed catalytically, generating enamine products which are amenable to subsequent hydrogenation reactions giving their corresponding amines. The chemistry is expanded to intramolecular systems forming N-heterocyclic compounds. Furthermore, a FLP route to stoichiometric hydrophosphination of alkynes is developed.