Catalytic Aerobic Chemoselective α-Oxidation of Acylpyrazoles en Route to α-Hydroxy Acid Derivatives
作者:Seiya Taninokuchi、Ryo Yazaki、Takashi Ohshima
DOI:10.1021/acs.orglett.7b01293
日期:2017.6.16
described. Acylpyrazoles, carboxylic acid oxidation state substrates, were efficiently oxidized under aerobic conditions using TEMPO as an oxygenating agent. The mild catalytic conditions of the present catalysis were amenable to late-stage α-oxidation of various pharmaceutical agents and natural products, leading to previously unreported α-hydroxyacidderivatives in short steps. Preliminary mechanistic
Nickel/Photoredox-Catalyzed Methylation of (Hetero)aryl Chlorides Using Trimethyl Orthoformate as a Methyl Radical Source
作者:Stavros K. Kariofillis、Benjamin J. Shields、Makeda A. Tekle-Smith、Michael J. Zacuto、Abigail G. Doyle
DOI:10.1021/jacs.0c02805
日期:2020.4.22
represents a valuable transformation, but typically requires harsh reaction conditions or reagents. We report a radical approach for the methylation of (hetero)aryl chlorides using nickel/photoredox catalysis wherein trimethyl orthoformate, a common laboratory solvent, serves as a methylsource. This method permits methylation of (hetero)aryl chlorides and acyl chlorides at an early and late stage with
Novel pyrrole-2-acetylamino compounds of the formula: ##STR1## and salts thereof, wherein R" is H, alkyl, (CH.sub.2).sub.n CO.sub.2 H, CH.sub.2 CH.sub.2 SCH.sub.3, (CH.sub.2).sub.4 NH.sub.2 or (CH.sub.2).sub.2 CONH.sub.2 ; and n is 1 or 2, which have the same analgesic and antiinflammatory utility as zomepirac, but with reduced liability toward gastrointestinal irritation, and esters of the compounds of the above formula which are useful as intermediates to make said compounds.