The intermolecular hydroamination of unactivated alkenes with simple dialkyl amines remains an unsolved problem in organic synthesis. Here we report a catalytic protocol for efficient additions of cyclic and acyclic secondary alkyl amines to a wide range of alkyl olefins with complete anti-Markovnikov regioselectivity. In this process, C–N bond formation proceeds through a key aminium radical cation intermediate that is generated via electron transfer between an excited state iridium photocatalyst and an amine substrate. These reactions are redox neutral, completely atom economical, exhibit broad functional group tolerance, and occur readily at room temperature under visible light irradiation. Certain tertiary amine products are formally endergonic relative to their constituent olefin and amine starting materials and thus are not accessible via direct coupling with conventional ground state catalysts.

Deracemization is an attractive strategy for asymmetric synthesis, but intrinsic energetic challenges have limited its development. Here, we report a deracemization method in which amine derivatives undergo spontaneous optical enrichment upon exposure to visible light in the presence of three distinct molecular catalysts. Initiated by an excited-state iridium chromophore, this reaction proceeds through a sequence of favorable electron, proton, and hydrogen-atom transfer steps that serve to break and reform a stereogenic C–H bond. The enantioselectivity in these reactions is jointly determined by two independent stereoselective steps that occur in sequence within the catalytic cycle, giving rise to a composite selectivity that is higher than that of either step individually. These reactions represent a distinct approach to creating out-of-equilibrium product distributions between substrate enantiomers using excited-state redox events.

A new strategy for catalytic deracemization is presented, wherein amine derivatives undergo spontaneous optical enrichment upon exposure to visible light in the presence of three distinct molecular catalysts. Initiated by an excited-state iridium chromophore, this reaction proceeds <i>via </i>a sequence of favorable electron, proton, and hydrogen atom transfer steps that serve to break and reform a stereogenic C–H bond. The enantioselectivity in these reactions is jointly determined by two independent stereoselective steps that occur in sequence within the catalytic cycle, giving rise to a composite selectivity that is higher than that of either step individually. These reactions represent a distinct and potentially general approach to creating out-of-equilibrium product distributions between substrate enantiomers using excited-state redox events.

A series of 19 different asymmetric catalysts were screened in an effort to identify the first chiral catalyst for the rearrangement of α-hydroxy imines to α-amino ketones involving a 1,2-carbon shift. Although aluminate complexes of VAPOL, VANOL, and 7,7′-tBu2VANOL were quite effective catalysts giving up to 88% ee, the ne plus ultra catalyst for this reaction was found to be a zirconium complex of VANOL which gives 97 to >99% ee for the majority of the substrates examined. An X-ray diffraction study of the catalyst reveals that the zirconium exists as a homoleptic complex with three VANOL ligands and two protonated N-methyl imidazoles.

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