72739-14-1

The reaction of N-Boc-α-amino acids with aryllithium reagents followed by removal of the nitrogen protecting group provides enantiomerically pure α-amino aryl ketones as their corresponding HCl salts. This practical two-step sequence gives rapid access to a pharmaceutically interesting class of compounds from commercially available starting materials.

Herein we disclose a new catalytic asymmetric approach for the synthesis of chiral α-Amino ketones, which is particularly useful for the less accessible acyclic α-Tertiary cases. By a protonation-Amination sequence, our approach represents a rare asymmetric H-heteroatom bond insertion by α-carbonyl sulfonium ylides, an attractive surrogate of diazocarbonyls. The mild intermolecular C-N bond formation was catalyzed by chiral phosphoric acids with excellent efficiency and enantioselectivity. The products are precursors to other important chiral amine derivatives, including drug molecules and chiral ligands. The enantioselectivity was controlled by dynamic kinetic resolution in the amination step, rather than the initial protonation. This process opens up a new platform for the development of other related insertion reactions.

Reaction of N-tert-butanesulfinyl α-halo imines with alkoxides afforded new N-tert-butanesulfinyl 2-amino acetals in good to excellent yield. These N-tert-butanesulfinyl 2-amino acetals are convenient precursors for the TMSOTf-promoted synthesis of the co

Both enantiomers of Cathinone were prepared as HCl salts from N-(R)-α-methylbenzylaziridine-2(S)-carboxaldehyde 2c and its enantiomer N-(S)-α-methyl-benzylaziridine-2(R)-carboxaldehyde 3c in high yield. This process makes it possible to prepare other aromatic and heteroaromatic analogs of Cathinone efficiently.

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