Reoptimization of the Organocatalyzed Double Aldol Domino Process to a Key Enal Intermediate and Its Application to the Total Synthesis of Δ12 -Prostaglandin J3.

Re-investigation of the l-proline catalyzed double aldol cascade dimerization of succinaldehyde for the synthesis of a key bicyclic enal intermediate, pertinent in the field of stereoselective prostaglandin synthesis, is reported. The yield of this process has been more than doubled, from 14 % to a 29 % isolated yield on a multi-gram scale (32 % NMR yield), through conducting a detailed study of the reaction solvent, temperature, and concentration, as well as a catalyst screen. The synthetic utility of this enal intermediate has been further demonstrated through the total synthesis of Δ12 -prostaglandin J3 , a compound with known anti-leukemic properties.

Crystal structure of 3-amino-5,5-dimethyl-2-[(E)-2-nitro-ethen-yl]cyclo-hex-2-en-1-one.

The asymmetric unit of the title compound, C10H14N2O3, contains two independent mol-ecules with similar conformations. In the both mol-ecules, the cyclo-hexene rings adopt the same envelope conformation with the flap C atoms lying 0.658 (3) and 0.668 (3) Šfrom the mean planes formed by the remaining atoms. In the crystal, adjacent mol-ecules are connected via N-H⋯O hydrogen bonds and weak C-H⋯O inter-actions, forming supra-molecular layers parallel to (-101).

Highly chemoselective copper-catalyzed conjugate reduction of stereochemically labile alpha,beta-unsaturated amino ketones.

Highly chemoselective conjugate reduction of chiral alpha,beta-unsaturated amino ketones has been developed by using triisopropyl phosphite ligated copper hydride complex. The highlights of the method are wide substrate compatibility and exceptional chemoselectivity.