Chiral Phosphoroamide Organocatalyzed Asymmetric Michael Addition Of Nitrostyrenes

In this thesis, we successfully proved that (thio)phosphorodiamides, as structural relatives of thioureas, can function as excellent bidentate hydrogen bond donors. Owing to the diversity of phosphorus compounds, the combination of this moiety with Br(?)nsted or Lewis base offers a great opportunity to develop of a novel type of bifunctional bidentate hydrogen bond donor organocatalysts.Starting from (1R,2R)-N,N-dimethylcyclohexane-1,2-diamine and (R)-or (S)-Betti base, a series of chiral catalysts based on (thio) phosphorodiamides was designed and synthesized. For comparison, a monodentate hydrogen bond donor catalyst thiophosphinamide was also prepared. Catalyst screening revealt that these newly designed catalysts demonstrate good catalytic activity and excellent ee value in the model reaction of Michael addition of 2-hydroxy-1,4-naphthoquinone toβ-nitrostyrene. In all cases, the reaction ran smoothly to afford the desired product in good yields in quite a short time. Among them, clohexane-1,2-diamine-based phenylphosphonothioicdiamide is the most promising catalyst candidate for this transformation. Under the optimal reaction conditions, almost perfect stereocontrol was achieved for both aliphatic and aromatic nitroolefins.In addition, the less reactive a-methylnitrostyrene, an interesting acceptor, since two contiguous tertiary stereocenters will be created in the Michael reaction, was also a good reaction partner, affording the desired product as a single diastereomer with an ee value of 91%.