New method for generation of β-oxido carbenoid via ligand exchange reaction of sulfoxides: A versatile procedure for one-carbon homologation of carbonyl compounds
one-carbon homologation of carbonylcompounds is described. The method is based on the rearrangement of β-oxido carbenoid which is generated via the ligand exchange reaction of the sulfinyl group of α-chloro β-hydroxy sulfoxide with tert-butyllithium. Addition of the carbanion of aryl 1-chloroalkyl sulfoxides to carbonylcompounds gave the adducts in good yields. The β-oxido carbenoid rearrangement of the
Abstract α-Arylated ketones were obtained in moderate to good yields by one-step electroreductive coupling of α-chloroketones and arylhalides in DMF and in the presence of a Al- or Zn-sacrificial anode and a catalytic amount of a nickel complex.
of aryl halides and activated alkylhalides in DMF in the presence of catalytic amount of NiBr(2)bipy leads to cross-coupling products in good to high yields. The method applies to the synthesis of alpha-aryl ketones, alpha-aryl esters, and allylated compounds from readily available organic halides. Optimization of the process has been obtained by slowly adding the most reactive organic halide (usually
Transition metal-free asymmetric and diastereoselective allylic alkylation using Grignard reagents: construction of vicinal stereogenic centers via kinetic resolution
作者:David Grassi、Alexandre Alexakis
DOI:10.1039/c4sc01003e
日期:——
The first transition metal-free diastereoselective and enantioselective asymmetricallylicalkylation (AAA) has been disclosed leading to the construction of vicinal tertiary/quaternary centers via a kinetic resolution protocol starting from readily available starting materials. This procedure is chemically appealing since no consecutive AAA or stereoselective metal-catalyzed/chiral ligand AAAs are
Allylations of aryl/heteroaryl ketones: neat, clean, and sustainable. Applications to targets in the pharma- and nutraceutical industries
作者:Xiaohan Li、Alex B. Wood、Nicholas R. Lee、Fabrice Gallou、Bruce H. Lipshutz
DOI:10.1039/d2gc00776b
日期:——
Aromatic and heteroaromatic ketones bearing an α-methine proton can be deprotonated and mono-allylated in minutes in the complete absence of an organic solvent to arrive at the corresponding products in high isolated yields. Applications to synthetic targets including both MK-7 and MK-9, as well as coenzyme Q9 (CoQ9), utilizing this new technology are documented.