Silver-catalyzed [3+3]-annulation cascade of alkynyl alcohols and α,β-unsaturated ketones for the regioselective assembly of chromanes

Gold-catalyzed intermolecular oxidation of carboxylates of primary or secondary propargylic alcohols are realized with excellent regioselectivity, which is ascribed to inductive polarization of the C–C triple bond by the electron-withdrawing carboxy group. The gold carbene intermediates thus generated undergo selective 1,2-acyloxy migration over a 1,2-C–H insertion, and the selectivities could be dramatically improved by the use of a P,S-bidentate ligand, which is proposed to enable the formation of tris-coordinated and hence less electrophilic gold carbene species. α-Carboxy α,β-unsaturated ketones/aldehydes can be obtained with fair to excellent yields.

Download Full-text

Chemoselective catalytic reduction of conjugated α,β-unsaturated ketones to saturated ketones via a hydroboration/protodeboronation strategy

Organic Chemistry Frontiers ◽

10.1039/c5qo00289c ◽

2016 ◽

Vol 3 (1) ◽

pp. 14-18 ◽

Cited By ~ 33

Author(s):

Wen Ding ◽

Qiuling Song

Keyword(s):

Metal Hydride ◽

Triple Bond ◽

Catalytic Reduction ◽

Hydrogen Gas ◽

Single Bond ◽

Unsaturated Ketones ◽

Reaction Proceeds

A novel copper-catalyzed chemoselective reduction of a carbon–carbon double or triple bond to a carbon–carbon single bond on α,β-unsaturated ketones is developed, this reaction proceeds under hydrogen gas or stoichiometric metal hydride free conditions.

Download Full-text

1,4-Reductions of α,β-Unsaturated Ketones and Aldehydes via in situ Generated Hydridocuprates

Synlett ◽

10.1055/s-1989-20359 ◽

1989 ◽

Vol 1989 (01) ◽

pp. 64-66 ◽

Cited By ~ 2

Author(s):

Bruce H. Lipshutz ◽

Christopher S. Ung ◽

Saumitra Sengupta

Keyword(s):

Unsaturated Ketones

Download Full-text

Silicon Assisted Halogenation I: A Convenient Synthesis of β-chloroketones via Reaction of α,β-unsaturated ketones with Tetrachlorosilane-Phenol

10.3390/ecsoc-13-00181 ◽

2009 ◽

Author(s):

Tarek Salama ◽

Saad Elmorsy

Keyword(s):

Unsaturated Ketones ◽

Convenient Synthesis

Download Full-text

On the Linear Geometry of Lanthanide Hydroxide (Ln—OH, Ln=La-Lu)

10.26434/chemrxiv.7851848.v3 ◽

2019 ◽

Author(s):

Hassan Harb ◽

Lee Thompson ◽

Hrant Hratchian

Keyword(s):

Triple Bond ◽

Density Functional ◽

Valence Electron ◽

Density Functional Theory Calculations ◽

Electron Configuration ◽

Functional Theory ◽

Key Species ◽

Pi Orbitals ◽

Lanthanide Hydroxide ◽

Linear Geometry

Lanthanide hydroxides are key species in a variety of catalytic processes and in the preparation of corresponding oxides. This work explores the fundamental structure and bonding of the simplest lanthanide hydroxide, LnOH (Ln=La-Lu), using density functional theory calculations. Interestingly, the calculations predict that all structures of this series will be linear. Furthermore, these results indicate a valence electron configuration featuring an occupied sigma orbital and two occupied pi orbitals for all LnOH compounds, suggesting that the lanthanide-hydroxide bond is best characterized as a covalent triple bond.

Download Full-text

On the Linear Geometry of Lanthanide Hydroxide (Ln—OH, Ln=La-Lu)

10.26434/chemrxiv.7851848 ◽

2019 ◽

Author(s):

Hassan Harb ◽

Lee Thompson ◽

Hrant Hratchian

Keyword(s):

Triple Bond ◽

Density Functional ◽

Valence Electron ◽

Density Functional Theory Calculations ◽

Electron Configuration ◽

Functional Theory ◽

Key Species ◽

Pi Orbitals ◽

Lanthanide Hydroxide ◽

Linear Geometry

Lanthanide hydroxides are key species in a variety of catalytic processes and in the preparation of corresponding oxides. This work explores the fundamental structure and bonding of the simplest lanthanide hydroxide, LnOH (Ln=La-Lu), using density functional theory calculations. Interestingly, the calculations predict that all structures of this series will be linear. Furthermore, these results indicate a valence electron configuration featuring an occupied sigma orbital and two occupied pi orbitals for all LnOH compounds, suggesting that the lanthanide-hydroxide bond is best characterized as a covalent triple bond.

Download Full-text