Synthesis of Difluoromethyl Ketones from Weinreb Amides, and Tandem Addition/Cyclization of <i>o</i>
-Alkynylaryl Weinreb Amides
作者:Jongkonporn Phetcharawetch、Nolan M. Betterley、Darunee Soorukram、Manat Pohmakotr、Vichai Reutrakul、Chutima Kuhakarn
DOI:10.1002/ejoc.201701322
日期:2017.12.15
[Difluoro(phenylsulfanyl)methyl]trimethylsilane (PhSCF2SiMe3) underwent a fluoride-induced nucleophilic addition to the carbonyl group of Weinreb amides to provide the corresponding difluoro(phenylsulfanyl)methyl ketones. These were converted into difluoromethyl ketones through selective reductive cleavage of the phenylsulfanyl group. The reaction of o-alkynyl Weinreb amides derived from benzoic acid derivatives resulted
Process for the production of fluorinated organic compounds and fluorinating agents
申请人:——
公开号:US20030176747A1
公开(公告)日:2003-09-18
A process for the production of a fluorinated organic compound, characterized by fluorinating an organic compound having a hydrogen atoms using IF
5
; and a novel fluorination process for fluorinating an organic compound having a hydrogen atoms by using a fluorinating agent containing IF
5
and at least one member selected from the group consisting of acids, bases, salts and additives.
IF5 in Et3N–3HF was found to be a stable, non-hazardous, easy to handle, and inexpensive reagent that enables effective and selective fluorination of organic compounds under mild conditions.
Switching Chemoselectivity: Using Mechanochemistry to Alter Reaction Kinetics
作者:Joseph L. Howard、Michael C. Brand、Duncan L. Browne
DOI:10.1002/anie.201810141
日期:2018.12.3
A reaction manifold has been discovered in which the chemoselectivity can be altered by switching between neat milling and liquid assisted grinding (LAG) with polar additives. After investigation of the reaction mechanism, it has been established that this switching in reaction pathway is due to the neat mechanochemical conditions exhibiting different kinetics for a key step in the transformation.
Mono- and difluorinations of sulfides were achieved using a novel fluorinating reagent, IF5–Et3N–3HF. The reagent is applicable for substrates having various electron-withdrawing groups, such as an ester, amide, ketone, nitrile, sulfone, or trifluoromethyl. Because more than one fluorine atom on IF5 is used, a large excess amount of the reagent is not necessary, even for the difluorination reaction.