Atom and step economical synthesis of acyclic quaternary centers via iridium-catalyzed hydroarylative cross-coupling of 1,1-disubstituted alkenes

Quaternary benzylic centers are accessed with high atom and step economy by Ir-catalyzed alkene hydroarylation. These studies provide unique examples of the use of non-polarized 1,1-disubstituted alkenes in branch selective Murai-type hydro(hetero)arylations. Detailed mechanistic studies have been undertaken, and these indicate that the first irreversible step is the demanding alkene carbometallation process. Structure-reactivity studies show that the efficiency of this is critically dependent on key structural features of the ligand. Computational studies have been undertaken to rationalize this experimental data, showing how more sterically demanding ligands reduce the reaction barrier via predistortion of the reacting intermediate. The key insight disclosed here will underpin the ongoing development of increasingly sophisticated branch selective Murai hydroarylations

Iridium-Catalyzed alpha-Selective Arylation of Styrenes by Dual C-H Functionalization

An IrI -system modified with a ferrocene derived bisphosphine ligand promotes α-selective arylation of styrenes by dual C-H functionalization. These studies offer a regioisomeric alternative to the Pd-catalyzed Fujiwara-Moritani reaction

Iridium-Catalyzed alpha-Selective Arylation of Styrenes by Dual C-H Functionalization

An IrI -system modified with a ferrocene derived bisphosphine ligand promotes α-selective arylation of styrenes by dual C-H functionalization. These studies offer a regioisomeric alternative to the Pd-catalyzed Fujiwara-Moritani reaction

Branch-Selective and Enantioselective Iridium-Catalyzed Alkene Hydroarylation via Anilide-Directed C–H Oxidative Addition

Tertiary benzylic stereocenters are accessed in high enantioselectivity by Ir-catalyzed branch selective addition of anilide <i>ortho</i>-C–H bonds across styrenes and α-olefins. Mechanistic studies indicate that the stereocenter generating step is reversible

Branch-Selective and Enantioselective Iridium-Catalyzed Alkene Hydroarylation via Anilide-Directed C–H Oxidative Addition

Tertiary benzylic stereocenters are accessed in high enantioselectivity by Ir-catalyzed branch selective addition of anilide <i>ortho</i>-C–H bonds across styrenes and α-olefins. Mechanistic studies indicate that the stereocenter generating step is reversible

Branch-Selective and Enantioselective Iridium-Catalyzed Alkene Hydroarylation via Anilide-Directed C–H Oxidative Addition

Tertiary benzylic stereocenters are accessed in high enantioselectivity by Ir-catalyzed branch selective addition of anilide <i>ortho</i>-C–H bonds across styrenes and α-olefins. Mechanistic studies indicate that the stereocenter generating step is reversible

Branch-Selective and Enantioselective Iridium-Catalyzed Alkene Hydroarylation via Anilide-Directed C–H Oxidative Addition

Tertiary benzylic stereocenters are accessed in high enantioselectivity by Ir-catalyzed branch selective addition of anilide <i>ortho</i>-C–H bonds across styrenes and α-olefins. Mechanistic studies indicate that the stereocenter generating step is reversible

Synthesis of Functionalized Cyanopyrazoles via Magnesium Bases

4-Alkyl- and 4-H-pyrazoles were sequentially metalated using TMPMgCl·LiCl, and their reaction with electrophiles afforded 3-aryl-4-alkyl-5-cyanopyrazoles