protocol for the reductive functionalization of amides into N‐sulfonylformamidines is reported. The one‐pot procedure is based on a mild catalyticreduction of tertiary amides into the corresponding enamines by the use of Mo(CO)6 (molybdenum hexacarbonyl) and TMDS (1,1,3,3‐tetramethyldisiloxane). The formed enamines were allowed to react with sulfonyl azides to give the target compounds in moderate to
secondary alkylamines with activemethylenecompounds afforded mono-sulfenylated compounds in good yields. The reactions of 2 mol of sulfenamides derived from imides with 1 mol of activemethylenecompounds in the presence of a base gave di-sulfenylated compounds. It was found that α-mono-sulfenylated ketones were prepared by the reactions of enamines with sulfenamides derived from imides. α-gem-Di-sulfenylated
Development of an Amine-Catalyzed Regioselective Synthesis of Pyrroles
作者:Taban K. K. Kakaawla、Joseph P. A. Harrity
DOI:10.1021/acs.orglett.7b03658
日期:2018.1.5
A regioselective synthesis of pyrroles has been devised through the cycloaddition of 1,3-oxazolium-5-olates and enamines. Product regiochemistry is controlled by the enamine substitution pattern. Moreover, an amine-catalyzed variant of this reaction allows aldehydes to be used directly as substrates for pyrrolesynthesis.
Synergistic Bimetallic Ni/Ag and Ni/Cu Catalysis for Regioselective γ,δ-Diarylation of Alkenyl Ketimines: Addressing β-H Elimination by in Situ Generation of Cationic Ni(II) Catalysts
作者:Prakash Basnet、Shekhar KC、Roshan K. Dhungana、Bijay Shrestha、Timothy J. Boyle、Ramesh Giri
DOI:10.1021/jacs.8b09401
日期:2018.11.21
We disclose unprecedented synergistic bimetallic Ni/Ag and Ni/Cu catalysts for regioselective γ,δ-diarylation of unactivated alkenes in simple ketimines with aryl halides and arylzinc reagents. The bimetallic synergy, which generates cationic Ni(II) species during reaction, promotes migratory insertion and transmetalation steps and suppresses β-H elimination and cross-coupling, the major side reactions
Mild and Selective Et<sub>2</sub>Zn-Catalyzed Reduction of Tertiary Amides under Hydrosilylation Conditions
作者:Oleksandr O. Kovalenko、Alexey Volkov、Hans Adolfsson
DOI:10.1021/ol503430t
日期:2015.2.6
(Et2Zn) can be used as an efficient and chemoselective catalyst for the reduction of tertiary amides under mild reaction conditions employing cost-effective polymeric silane (PMHS) as the hydride source. Crucial for the catalytic activity was the addition of a substoichiometric amount of lithium chloride to the reaction mixture. A series of amides containingdifferent additional functionalgroups were reduced