Oxidation of Primary Aliphatic and Aromatic Aldehydes with Difluoro(aryl)-λ3-bromane
摘要:
Oxidation of primary aliphatic aldehydes with p-trifluoromethylphenyl(difluoro)-lambda(3)-bromane in dichloromethane at 0 degrees C afforded acid fluorides selectively In good yields, while that of aromatic aldehydes In chloroform at room temperature produced aryl difluoromethyl ethers. A larger migratory aptitude of aryl groups compared to primary alkyl groups during a 1,2-shift from carbon to an electron-deficient oxygen atom in bromane(III) Criegee-type intermediates will result in these differences in the reaction courses.
[EN] CATALYTIC ASYMMETRIC SYNTHESIS OF OPTICALLY ACTIVE alpha-HALO-CARBONYL COMPOUNDS<br/>[FR] SYNTHESE ASYMETRIQUE CATALYTIQUE DE COMPOSES DE DOLLAR G(A)-HALO-CARBONYLE OPTIQUEMENT ACTIFS
申请人:HALLAND NIS
公开号:WO2005080298A1
公开(公告)日:2005-09-01
A process for the catalytic asymmetric synthesis of an optically active compound of the formula (la) or (lb): wherein R is an organic group; X is halogen; Rl and R2which may the same or different represents H, or an organic group or Rl and R2 may be bridged together forming part of a ring system; R and R2 may be bridged together forming part of a ring system; with the provisio that R and Rl are different and R2, when different from H, is attached though a carbon-carbon bond, comprising the step of reacting a compound of the formula (2): with a halogenation agent in the presence of a catalytic amount of a chiral nitrogen containing organic compound.
Versatile Palladium-Catalyzed Approach to Acyl Fluorides and Carbonylations by Combining Visible Light- and Ligand-Driven Operations
作者:Yi Liu、Cuihan Zhou、Meijing Jiang、Bruce A. Arndtsen
DOI:10.1021/jacs.2c01951
日期:2022.6.1
We describe the development of a general palladium-catalyzed carbonylative method to synthesize acyl fluorides from aryl, heteroaryl, alkyl, and functionalized organic halides. Mechanistic analysis suggests that the reaction proceeds via the synergistic combination of visible light photoexcitation of Pd(0) to induce oxidative addition with a ligand-favored reductive elimination. These together create
CATALYTIC ASYMMETRIC SYNTHESIS OF OPTICALLY ACTIVE ALPHA-HALO-CAR BONYL COMPOUNDS
申请人:Cheminova A/S
公开号:EP1716088A1
公开(公告)日:2006-11-02
Catalytic Asymmetric Synthesis of Optically Active Alpha-Halo-Carbonyl Compounds
申请人:Halland Nis
公开号:US20070276142A1
公开(公告)日:2007-11-29
A process for the catalytic asymmetric synthesis of an optically active compound of the formula (1a) or (1b)
wherein R is an organic group; X is halogen; R
1
and R
2
which may the same or different represents H, or an organic group or R
1
and R
2
may be bridged together forming part of a ring system; R and R
2
may be bridged together forming part of a ring system; with the provisio that R and R
1
are different and R
2
, when different from H, is attached though a carbon-carbon bond,
comprising the step of reacting a compound of the formula (2)
with a halogenation agent in the presence of a catalytic amount of a chiral nitrogen containing organic compound.
Oxidation of Primary Aliphatic and Aromatic Aldehydes with Difluoro(aryl)-λ<sup>3</sup>-bromane
Oxidation of primary aliphatic aldehydes with p-trifluoromethylphenyl(difluoro)-lambda(3)-bromane in dichloromethane at 0 degrees C afforded acid fluorides selectively In good yields, while that of aromatic aldehydes In chloroform at room temperature produced aryl difluoromethyl ethers. A larger migratory aptitude of aryl groups compared to primary alkyl groups during a 1,2-shift from carbon to an electron-deficient oxygen atom in bromane(III) Criegee-type intermediates will result in these differences in the reaction courses.