A general iron-catalyzed strategy for the atom-transfer radical cyclization (ATRC) of allylic halide is reported. Critical to this strategy is the use of DPPF [1,1'-bis(diphenylphosphino)ferrocene] as catalyst, which allows for efficient generation of the allylic radical species via a single-electron transfer (SET) process. The feasibility of achieving ATRC reactions of propargyl chlorides is also demonstrated, which affords products with an exocyclic allene moiety.

A copper-catalyzed annulation of oxime acetates and α-amino acid ester derivatives for the easy preparation of 4-pyrrolin-2-ones bearing a 3amino group has been developed. This process features the oxidation of amines with oxime esters as the internal oxidant to produce the active 1,3dinucleophilic and 1,2-dielectrophilic species concurrently. The subsequent nucleophilic cyclization realizes the efficient construction of 4-pyrrolin-2-one derivatives.

A Cu­(OAc)2-promoted cascade reaction of malonate-tetherd acyl oximes with indoles, indole-2-alcohols, or indole-2-carboxmides provides facile access to polysubstituted 3-pyrrolin-2-ones. The reaction features the generation of two adjacent electrophilic centers at the same time as cyclization to lactam. The subsequent double addition with nucleophiles followed by oxidation realizes the difunctionalization of the imine sp2-carbon and the adjacent α-sp3-carbon.

A Cu­(OAc)2-promoted oxidative cross-dehydrogenative coupling reaction of α-acylmethyl malonates with indole derivatives was developed. In the case of indoles, the regioselective coupling products were formed through a sequential dehydrogenation–addition–dehydrogenation process. When a second nucleophilic center was located in the 2-position of indoles, further successive nucleophilic cyclization occurred to give polycyclic indole derivatives. The Cu­(OAc)2 was proved to act as not only an oxidant but also a catalyst.

Although the Heck reactions of alkene partners with various electrophiles have achieved great success, the variant focused on carbon�heteroatom counterparts still remains elusive. Herein, we report a Pd(0)-catalyzed asymmetric intramolecular hydrazone-type Heck reaction of N-[(Z)-3-iodoallyl]-aminoacetaldehyde and hydrazine hydrate (NH 2 NH 2 −H 2 O), wherein the required hydrazone is in situ generated via an acid-promoted condensation. A key strategic advantage of this Heck paradigm is that the resultant Heck product allylic diazene rapidly undergoes stereospecific denitrogenative [1,5]-sigmatropic rearrangement, eventually furnishing a domino sequence toward 3-substituted tetrahydropyridine (THP) with high enantioselectivity. The substrate-induced diastereoselective version has also been realized, exclusively giving cis-2,5-disubstituted THPs. The utility of this sequence is demonstrated by the formal synthesis of multiple valuable bioactive targets, including 3-ethylindoloquinolizine, preclamol, and niraparib.