A novel Ni/photoredox-catalyzed acylation of aliphatic substrates, including simple alkanes and dialkyl ethers, has been developed. The method combines C–N bond activation of amides with a radical relay mechanism involving hydrogen-atom transfer. The protocol is operationally simple, employs bench-stable N-acyl imides as acyl-transfer reagents, and permits facile access to alkyl ketones under very
Arylation of Aldehydes To Directly Form Ketones via Tandem Nickel Catalysis
作者:Chuanhu Lei、Daoyong Zhu、Vicente III Tiu Tangcueco、Jianrong Steve Zhou
DOI:10.1021/acs.orglett.9b01782
日期:2019.8.2
both aliphatic and aromatic aldehydes proceeds with air-stable (hetero)arylboronic acids, with an exceptionally wide substrate scope. The neutral condition tolerates acidic hydrogen and sensitive polar groups and also preserves α-stereocenters of some chiral aldehydes. Interestingly, this nickel(0) catalysis does not follow common 1,2-insertion of arylmetal species to aldehydes and β-hydrogen elimination
Ketones are a fundamental functionality found throughout a range of natural and synthetic compounds, making their synthesis essential throughout the chemical disciplines. Herein, we describe a one-pot synthesis of ketones via decatungstate-mediated formal dehydrogenative coupling between aldehydes and non-activated hydrocarbons. A variety of substituted benzaldehydes and cycloalkanes could be used
The present invention provides a compound of Formula (I)
or a pharmaceutically acceptable salt thereof wherein R
1
, R
2
, R
3
, A
1
, A
2
, A
3
, A
4
, L, B
1
, B
2
, B
3
and B
4
are as defined herein. The compounds of Formula I have been found to act as glucagon antagonists or inverse agonists. Consequently, the compounds of Formula I and the pharmaceutical compositions thereof are useful for the treatment of diseases, disorders, or conditions mediated by glucagon.
Chemoselective synthesis of ketones and ketimines by addition of organometallic reagents to secondary amides
作者:William S. Bechara、Guillaume Pelletier、André B. Charette
DOI:10.1038/nchem.1268
日期:2012.3
is of great importance, as this motif serves as a synthetic handle for the elaboration of numerous organic functionalities. In this context, we report a general and chemoselective method based on an activation/addition sequence on secondaryamides allowing the controlled isolation of structurally diverse ketones and ketimines. The generation of a highly electrophilic imidoyl triflate intermediate was