Borylation Of Alkynes Research Articles

Copper-Catalyzed Regiodivergent Borylation of Fluorinated Alkynes and Palladium-Catalyzed Regiospecific Suzuki–Miyaura Cross-Coupling

AbstractAlkenylboranes are key intermediates in modern organic synthesis, and they are usually obtained by the borylation of alkynes. We report herein highly regio- and stereoselective syntheses of α,Z- and β,Z-trifluoromethylated alkenylboranes by copper-catalyzed borylation reactions. Further functionalizations by palladium-catalyzed Suzuki–Miyaura cross-couplings have been developed and, interestingly, a marked difference in reactivity between the α- and β-borylated isomers has been identified.

Regioselective catalytic carbonylation and borylation of alkynes with aryldiazonium salts toward α-unsubstituted β-boryl ketones.

A new Pd/Cu-catalyzed carbonylation and borylation of alkynes with aryldiazonium salts toward α-unsubstituted β-boryl ketones with complete regioselectivity has been developed. This transformation shows broad substrate scope and excellent functional-group tolerance. Moreover, the obtained 1,2-carbonylboration products provide substantial opportunities for further transformations which cannot be obtained by known carbonylation procedures. Preliminary mechanistic studies indicate that the three hydrogen atoms of the products originated from ethyl acetate.

Aluminum-Catalyzed Borylation of Alkynes

Aluminum-Catalyzed Borylation of Alkynes

Aluminium-Catalyzed C(sp)-H Borylation of Alkynes.

Historically used in stoichiometric hydroalumination chemistry, recent advances have transformed aluminium hydrides into versatile catalysts for the hydroboration of unsaturated multiple bonds. This catalytic ability is founded on the defining reactivity of aluminium hydrides with alkynes and alkenes: 1,2‐hydroalumination of the unsaturated π‐system. This manuscript reports the aluminium hydride catalyzed dehydroborylation of terminal alkynes. A tethered intramolecular amine ligand controls reactivity at the aluminium hydride centre, switching off hydroalumination and instead enabling selective reactions at the alkyne C−H σ‐bond. Chemoselective C−H borylation was observed across a series of aryl‐ and alkyl‐substituted alkynes (21 examples). On the basis of kinetic and density functional theory studies, a mechanism in which C−H borylation proceeds by σ‐bond metathesis between pinacolborane (HBpin) and alkynyl aluminium intermediates is proposed.

Aluminium‐Catalyzed C(sp)−H Borylation of Alkynes

AbstractHistorically used in stoichiometric hydroalumination chemistry, recent advances have transformed aluminium hydrides into versatile catalysts for the hydroboration of unsaturated multiple bonds. This catalytic ability is founded on the defining reactivity of aluminium hydrides with alkynes and alkenes: 1,2‐hydroalumination of the unsaturated π‐system. This manuscript reports the aluminium hydride catalyzed dehydroborylation of terminal alkynes. A tethered intramolecular amine ligand controls reactivity at the aluminium hydride centre, switching off hydroalumination and instead enabling selective reactions at the alkyne C−H σ‐bond. Chemoselective C−H borylation was observed across a series of aryl‐ and alkyl‐substituted alkynes (21 examples). On the basis of kinetic and density functional theory studies, a mechanism in which C−H borylation proceeds by σ‐bond metathesis between pinacolborane (HBpin) and alkynyl aluminium intermediates is proposed.

A New Fluoroalkylation–Borylation of Alkynes

A New Fluoroalkylation–Borylation of Alkynes

ChemInform Abstract: Borylation of Alkynes under Base/Coinage Metal Catalysis: Some Recent Developments

AbstractReview: 104 refs.

Borylation of Alkynes under Base/Coinage Metal Catalysis: Some Recent Developments

Alkenylboranes have been vital reagents in modern synthetic organic chemistry, whose carbon–boron bond is transformable into a carbon–carbon bond stereoretentively to give such invaluable mutisubstituted alkenes as natural products, biologically active molecules, and functional materials. Introduction of a boryl moiety across a carbon–carbon triple bond of alkynes (borylation of alkynes) is one of the most direct and potent methods for synthesizing alkenylboranes, and this field has thus far experienced remarkable progress mainly with group 10 transition metal catalysts (Ni, Pd, Pt), which enables highly functionalized alkenylboranes to be constructed stereoselectively. On the other hand, much attention has recently been focused on the appealing catalysis of base (Fe, Co) and coinage (Cu, Ag, Au) metals toward the borylation of alkynes, which is summarized in this perspective.

ChemInform Abstract: A Masked Diboron in Cu‐Catalyzed Borylation Reaction: Highly Regioselective Formal Hydroboration of Alkynes for Synthesis of Branched Alkenylborons.

AbstractA series of alkenylboron products (III) is readily prepared by a copper‐catalyzed borylation of alkynes (I).

Borylation of Alkynes with MgO-Supported CuO or Pt Nanoparticles

Borylation of Alkynes with MgO-Supported CuO or Pt Nanoparticles