The asymmetric synthesis of tricyclic compounds by the desymmetrization of cyclohexadienones is presented. The reaction tolerated a large variety of substituents at different positions of the cyclohexadienone, and heterocyclic rings of different sizes were accessible. Density functional theory calculations showed that the reaction proceeds through an asynchronous [4+2] cycloaddition.

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Pull the trigger! The use of (Z)‐β,β‐bromo‐nitroalkenes under enamine catalysis provides the 1,4‐Michael adduct intermediate, which upon treatment with the desired amine (R3NH2) triggers the domino reaction to provide the final 3,4‐disubstituted pyrrole derivatives.

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The asymmetric synthesis of tricyclic compounds by the desymmetrization of cyclohexadienones is presented. The reaction tolerated a large variety of substituents at different positions of the cyclohexadienone, and heterocyclic rings of different sizes were accessible. Density functional theory calculations showed that the reaction proceeds through an asynchronous [4+2] cycloaddition.

The use of a catalytic amount of platinum complexes (1 mol %) was found to be compatible with different organocatalysts (DABCO or the Jørgensen-Hayashi catalyst) that were used in the functionalization of various activated methylenes. By this method, a series of lactones with C-3 quaternary centers and substitution at C-5 were prepared.

Highly Enantioselective Construction of Tricyclic Derivatives by the Desymmetrization of Cyclohexadienones. -(MARTIN-SANTOS, C.; JARAVA-BARRERA, C.; DEL POZO, S.; PARRA, A.; DIAZ-TENDERO, S.; MAS-BALLESTE, R.; CABRERA, S.; ALEMAN*, J.; Angew. Chem., Int. Ed. 53 (2014) 31, 8184-8189, http://dx.

A new organocatalytic synthesis of 3,4‐disubstituted pyrroles is presented, involving the one‐pot, two‐step reaction of aldehydes, e.g. (I), with gem‐bromonitroalkenes, e.g. (II), and amines, e.g. (III).