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Owing to their inexpensive and environmentally friendly properties, iron-based catalysts have been actively investigated for new organic reactions. In this account, we summarized our recent results on iron-catalyzed cross-coupling reactions and homo-coupling reactions. With iron-based catalysts, we constructed diverse carbon-carbon bonds, i.e., C(sp2)−C(sp3), C(sp3)−C(sp3), C(sp3)−C(sp2) and C(sp2)−C(sp2) bonds. In order to demonstrate the usefulness of our iron protocol, we also carried out these reactions on gram-scale reactions, leading to good yields

A new strategy was developed for the efficient synthesis of di-, tetra-, and hexa-substituted 1,3-butadienes. This one-pot procedure involves lithium–iodine exchange to generate the corresponding vinyllithium intermediates. A subsequent iron-catalyzed ligand-free oxidative homo-coupling eventually led to the formation of 1,3-butadienes in acceptable to excellent isolated yields.

Three pivotal reactions, namely, enyne cycloisomerization, polyene cyclization, and quinone methide formation, are applied to synthesize the complex polycyclic skeleton of cryptotrione. This review summarizes the most prominent applications of these three reactions to the total syntheses of natural products, covering results published in the literature between 2011 and 2020.1 Introduction2 Three Pivotal Reactions Applied to Create the Polycyclic Framework of Cryptotrione2.1 Enyne Cycloisomerization2.2 Polyene Cyclization2.3 Quinone Methide Formation3 Conclusion

A strategy for the synthesis of multisubstituted hydrocarbazoles has been developed through (3 + 2)-annulation of p-quinamines and arynes. In this way, new analogs of hydrocarbazoles with quaternary carbon center can be synthesized in satisfactory yield under mild conditions. Furthermore, this (3 + 2)-annulation can be easily scaled-up, and the products can be modified through simple transformation.

A new strategy was developed for the efficient synthesis of di-, tetra-, and hexa-substituted 1,3-butadienes. This one-pot procedure involves lithium-iodine exchange to generate the corresponding vinyllithium intermediates. A subsequent iron-catalyzed ligand-free oxidative homo-coupling eventually led to the formation of 1,3-butadienes in acceptable to excellent isolated yields.

A protecting-group-free route for the total synthesis of (-)-lycopodine was demonstrated in only 8 steps from Wade's fawcettimine enone (12 steps from commercial availiable (R)-(+)-pulegone). The key core of this alkaloid was constructed through a phosphoric acid promoted and highly stereocontrolled alkyne aza-Prins cyclization reaction, synchronously establishing the bridged B-ring and the C13 quaternary stereocenter. Importantly, the synthesis further features a new efficient approach for the preparation of other lycopodine-type alkaloids.

The first bioinspired total syntheses of (-) kravanhins A and C were accomplished from a labdane diterpenoid derivative. The key reactions involve a photooxidation and a one-pot sequential aldol cyclization and lactonization, which provide a new plausible biosynthetic pathway for the kravanhins and other symbiotic members.

The first asymmetric total synthesis of kravanhin B has been accomplished with a linear reaction sequence of 13 steps starting from (R)-(-)-carvone. The synthesis features an intramolecular aldol cyclization to construct the desired cis-fused decalin skeleton and an acid-catalyzed dehydration and olefin isomerization to install the γ-butenolide ring.

The first total synthesis of isospongian diterpenoid (+/-)-polyrhaphin D has been accomplished in 9 steps with 19% overall yield starting from the Wieland-Miescher ketone derivative. The key features of our synthesis include a sequential reduc-tion/Michael addition/aldol condenzation to assemble the A ring and an intramolecular dehydrative cyclization/olefin isomerization reaction to install the gamma-butenolide D ring.

A visible-light-promoted, mild, and direct difunctionalization of alkynoates has been accomplished. This procedure provides a new strategy toward synthesis of the coumarin core structure by photoredox-mediated oxidation to generate the α-oxo radical, which supervenes a domino radical addition/cyclization reaction in moderate to good yields with high regioselectivity at ambient temperature.

In order to avoid the aggregation and/or fusion of the polyelectrolyte multilayer hollow microcapsules self-assembled via the noncovalent bonds, superparamagnetic polyelectrolyte hybrid hollow microcapsules surface-modified with polyethylene glycol (PEG) brushes were designed and fabricated. After the layer-by-layer (LbL) self-assembly of chitosan (CS) and citric acid-modified magnetic nanoparticles (Fe3O4–CA) as the polycation and the hybrid anion on the polystyrene sulfonate microsphere (PSS) templates, respectively, the aldehyde group terminated polyethylene glycol-4000 (APEG) was grafted onto the surface of the superparamagnetic polyelectrolyte hybrid multilayer coated template microspheres via the nucleophilic addition between the aldehyde groups of APEG and the amino groups of CS. Then, the modified superparamagnetic polyelectrolyte hybrid hollow microcapsules were obtained after the templates were removed by dialysis. It was found that the surface PEGylation could prevent aggregation among the holl...

A visible-light-promoted, mild, and direct difunctionalization of alkynoates has been accomplished. This procedure provides a new strategy toward synthesis of the coumarin core structure by photoredox-mediated oxidation to generate the α-oxo radical, which supervenes a domino radical addition/cyclization reaction in moderate to good yields with high regioselectivity at ambient temperature.

We present the application of a bioinspired collective synthesis strategy in the total syntheses of seven iboga-type indole alkaloids: (±)-tabertinggine, (±)-ibogamine, (±)-ibogaine, (±)-ibogaine hydroxyindolenine, (±)-3-oxoibogaine hydroxyindolenine, (±)-iboluteine, and (±)-ervaoffines D. In particular, tabertinggine and its congeners serve as iboga precursors for the subsequent biomimetic transformations into other iboga-type alkaloids.

Ring around the rosie: The effective enantioselective synthesis of the antimalarial nonenolide title compounds was achieved in a convergent strategy. Oxy-Michael addition reaction was used to introduce the chiral methoxy group at C-4, and ring-closing metathesis (RCM) reaction (53 % yield) facilitated the key construction of the 10-membered ring.