Asymmetric catalysis for chiral compound synthesis is a rapidly growing field in modern organic chemistry. Asymmetric catalytic processes have been indispensable for the synthesis of enantioselective materials to meet demands from various fields. Michael addition has been used extensively for the construction of C-C bonds under mild conditions. With the discovery and development of organo- and metal-catalyzed asymmetric Michael additions, the synthesis of enantioselective and/or diastereoselective Michael adducts has become possible and increasingly prevalent in the literature. In particular, metal-catalyzed asymmetric Michael addition has been employed as a key reaction in natural product synthesis for the construction of contiguous quaternary stereogenic center(s), which is still a difficult task in organic synthesis. Previously reported applications of metal-catalyzed asymmetric Michael additions in natural product synthesis are presented here and discussed in depth.

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The synthetically challenging, diverse chemical skeletons and promising biological profiles of the Daphniphyllum alkaloids have generated intense interest from the synthetic chemistry community. Herein, the first and enantioselective total synthesis of (−)-caldaphnidine O, a complex bukittinggine-type Daphniphyllum alkaloid, is described. The key transformations in this concise approach included an intramolecular aza-Michael addition, a ring expansion reaction sequence, a Sm(II)/ Fe(III)-mediated Kagan−Molander coupling, and the rapid formation of the entire hexacyclic ring skeleton of the target molecule via a radical cyclization cascade reaction, which was inspired by an unexpected radical detosylation observed in our recent dapholdhamine B synthesis.

By using N,N-dimethylformamide (DMF) as am ethylenating reagent, the copper-catalyzed C À Ha ctivation of indole was demonstrated as an efficient and facile protocolf or synthesizing 3,3'-diindolylmethane (DIM)a nd its derivatives.T he results indicatet hat copper chloride was the best catalyst among the investigatedt ransitionm etal salts, which affords an excellent regioselectivity and good yield when tert-butyl hydroperoxide (TBHP) was used as an oxidant.

A simple ruthenium‐catalyzed conjugate addition of C−H bonds to α,β‐unsaturated ketones directed by a removable carboxyl group was developed as an effective protocol to synthesize ortho‐alkylated benzoic acids in a greener manner. Without any additives, satisfactory to excellent yields of the targeted products were achieved in neat water, and the process characterizes in mild reaction conditions (in air and water), simple operations, and broad substrate scope. Noteworthy features of this method include mild reaction conditions (in air and water), operational simplicity and broad substrate scope. The versatility and utility of the addition products were demonstrated through further transformation into commonly inaccessible but highly useful motifs of meta‐substituted alkylbenzenes and 3‐substituted isochromanones.magnified image