Reversal of polarity by catalytic SET oxidation: synthesis of azabicyclo[<i>m</i>.<i>n</i>.0]alkanes <i>via</i> chemoselective reduction of amidines
作者:Kirana Devarahosahalli Veeranna、Kanak Kanti Das、Sundarababu Baskaran
DOI:10.1039/d1ob00416f
日期:——
A one-pot catalytic method has been developed for the stereoselective synthesis of cyclopropane-fused cyclic amidines using CuBr2/K2S2O8 as an efficient single electron transfer (SET) oxidative system. The generality of this mild method is demonstrated with a wide variety of substrates to furnish pharmaceutically important amidines containing aza-bicyclic and novel aza-tricyclic frameworks in very
使用CuBr 2 /K 2 S 2 O 8作为有效的单电子转移(SET)氧化体系,开发了一种用于立体选择性合成环丙烷稠合环脒的单锅催化方法。这种温和方法的普遍性通过多种底物得到证明,以非常好的收率提供含有氮杂-双环和新型氮杂-三环骨架的药学上重要的脒。将环脒化学选择性还原为 2-/3-氮杂双环[ m . n .0]烷烃和八氢吲哚已使用 NaBH 4 /I 2开发试剂系统。化学选择性还原脒官能团的合成范围已在基于亚氨基糖的 (±)-表喹酰胺类似物的立体选择性合成中得到例证。
Copper-Catalyzed Cyclization/aza-Claisen Rearrangement Cascade Initiated by Ketenimine Formation: An Efficient Stereocontrolled Synthesis of α-Allyl Cyclic Amidines
and convenient synthesis of α‐allyl cyclic amidines has been achieved by applying a novel cascade reaction. Copper(I)‐mediated in situ N‐sulfonyl ketenimine formation from the reaction of a terminal alkyne with sulfonyl azide is followed by an intramolecular nucleophilic attack on the central carbon atom by an allylic tertiary amine, and then an aza‐Claisen rearrangement takes place through a chair
A selective oxy-alkylation of allylamines with unactivated alkylbromides and CO2 via visible-light-driven palladium catalysis is reported. The commercially available Pd(PPh3)4 is used as the sole catalyst in this three-component reaction. A variety of tertiary, secondary, and primaryalkylbromides undergo reactions to generate important 2-oxazolidinones in high yields and selectivity. The mild reaction
1,1-Disubstituted and trisubstituted alkenes were converted into the corresponding β,γ-unsaturated amines 4 via three steps: the initial formation of α,β-unsaturated diphenylsulfonium triflates 2 from alkenes and diphenyl(trifluoromethanesulfonyloxy)sulfonium trifluoromethanesulfonate (1), followed by double bond migration of 2 to β,γ-unsaturated sulfonium triflates 3 with primary or secondary amines