Copper-Catalyzed [3 + 2 + 1] Cycloaddition of Alkenes with Benzoquinones and Dicarbonyl Compounds via Tandem Oxidative Dicarbofunctionalization/Cyclization Sequence

Developed is an efficient three-component [3 + 2 + 1] cycloaddition of simple alkenes with two C—H substrates via oxidative dicarbofunctionalization/cyclization sequence. The copper-catalyzed reaction involves the formation of two C—C bonds and one C—O bond through the cleavage of three C—H bonds in a single operation. The method has an excellent functional group tolerance, and features a broad substrate scope, affording a variety of functionalized chromenes in good yields.

Stereoselective 1,2-Dicarbofunctionalization of Trisubstituted Alkenes by Palladium-Catalyzed Heck/Suzuki or Heck/Sonogashira Domino Sequence

Highly enantioselective and diastereoselective 1,2-diarylation and 1,2-arylalkynylation of trisubstituted alkenes are reported via the palladium-catalyzed Heck/Suzuki or Heck/Sonogashira domino sequence.These alkenes represent an extension of enantioselective dicarbofunctionalization from terminal alkenes to trisubstituted ones based on anionic capture of the secondary alkyl-Pd intermediate.

Enantioselective Synthesis ofα-Alkenylatedγ-Lactam Enabled by Ni-Catalyzed 1,4-Arylcarbamoylation of 1,3-Dienes

The facile construction of chiral quaternaryα-alkenylated pyrrolidinones is a long-term challenge in organic synthesis.The asymmetric difunctionalization of 1,3-dienes represents the most compelling tool for assembling alkenylated compounds by regioselective 1,2-or 1,4-difunctionalization.Nevertheless,the manipulation of unactivated 1,3-dienes to forge the quarternary stereogenic center still remains largely underdeveloped.Herein,we disclose a nickelcatalyzed asymmetric 1,4-arylcarbamoylation of unactivated 1,3-dienes tethered on carbamoyl fluoride with readily available arylboronic acids,providing rapid access to the enantioenrichedα-alkenylated pyrrolidinones bearing the quaternary stereogenic center in high yields with broad functional group tolerance.Moreover,this chiral ligand-controlled asymmetric transformation overcomes the intrinsic substrate control with a preexisting chiral center.

Nickel-Catalyzed Reductive Asymmetric Aryl-Acylation and Aryl-Carbamoylation of Unactivated Alkenes

Herein we report a nickel-catalyzed asymmetric two-component reductive aryl-acylation and arylcarbamoylation of aryl-iodide-tethered unactivated alkenes,which utilize ortho-pyridinyl esters and isocyanates as the electrophilic acyl sources,respectively.Under the catalysis of a nickel–pyrox complex with zinc powder as the reductant,a variety of chiral indanes,indolines,and dihydrobenzofurans bearing a quaternary stereogenic center were prepared in moderate to high efficiency and good to excellent enantioselectivities.The utility of this method is demonstrated by various simple derivatizations of the attached carbonyl group,particularly the sequential benzylic oxidation and pinacol coupling,which provide a concise entry to the benzene-fused bicyclic bridged ring framework containing three challenging tetrasubstituted stereocenters in high stereocontrol.