A Highly anti-Selective Asymmetric Henry Reaction Catalyzed by a Chiral Copper Complex: Applications to the Syntheses of (+)-Spisulosine and a Pyrroloisoquinoline Derivative

A highly anti‐selective asymmetric Henry reaction has been developed, affording synthetically versatile β‐nitroalcohols in a predominately anti‐selective manner (mostly above 15:1) and excellent ee values (mostly above 95 %). Moreover, the anti‐selective Henry reaction was carried out in the presence of water for the first time with up to 99 % ee. The catalytic mechanism was proposed based on the detection of the intermediates by extractive electrospray ionization mass spectrometry (EESI‐MS). Furthermore, the anti adducts have been successfully transformed into the biochemically important (+)‐spisulosine and a pyrroloisoquinoline derivative. Friendly water: An asymmetric Henry reaction that affords synthetically versatile β‐nitroalcohols in an anti‐selective manner and with excellent ee values has been developed (see scheme). The reaction was carried out in water for the first time with up to 99 % ee, and the anti‐adducts were successfully transformed into the biochemically important (+)‐spisulosine and a pyrroloisoquinoline derivative.