Rh<sup>III</sup>-Catalyzed Dehydrogenative Coupling of Quinoline<i>N</i>-Oxides with Alkenes:<i>N</i>-Oxide as Traceless Directing Group for Remote C-H Activation
A RhIII-catalyzeddehydrogenativecoupling reaction of quinoline N-oxides with alkenes has been developed that provides C-8 olefinated quinoline derivatives by employing a remoteC–Hactivation strategy. Main features of this catalytic method include the use of N-oxide as a tracelessdirectinggroup, the high selectivity of the reaction for the C-8 position, and the broad scope of possible substrates
PyridineN‐oxide–BF2CF3 and –BF2C2F5 complexes and their derivatives were synthesized. Most of the complexes show fluorescence both in solution and in the solid state. By expanding the π‐conjugated skeleton, the color of the fluorescence could be changed dramatically. A fluorophore with a high solvent dependency could also be produced. Since such compounds can be synthesized on a gram scale in high
amination/annulation strategy was developed for the synthesis of benzophenanthroline derivativesusing quinoline N‐oxides and anthranils. The method was further extended to the synthesis of nitrogen‐containing extended π‐conjugated benzophenanthrolinone derivatives. Late‐stage functionalizations of cinchonidine and cinchophen derivatives and synthesis of a bioactive quinolino‐indole were achieved.
Reduction of Hydrazines, Azo and Azoxy Compounds, and Amine N-Oxides with the NiCl2·2H2O–Li–DTBB (cat.) Combination
作者:Francisco Alonso、Gabriel Radivoy、Miguel Yus
DOI:10.1016/s0040-4020(00)00797-3
日期:2000.10
The NiCl2·2H2O/Li/DTBB (10 mol%) combination allows the reduction of aromatic hydrazines 1 (to amines), azo compounds 2 (to primary amines), azoxycompounds 3 (to azo compounds or to primary amines, depending on the reaction conditions) or amineN-oxides 4 (to tertiary amines), under mild reaction conditions (THF, room temperature).
通过使用NiCl 2 ·2H 2 O / Li / DTBB(10 mol%)的组合,可以还原芳香肼1(还原为胺),偶氮化合物2(还原为伯胺),偶氮化合物3(还原为偶氮化合物或伯胺), (取决于反应条件)或胺N-氧化物4(成叔胺),在温和的反应条件下(THF,室温)。
Regioselective Introduction of Heteroatoms at the C-8 Position of Quinoline <i>N</i>-Oxides: Remote C–H Activation Using <i>N</i>-Oxide as a Stepping Stone
Reported herein is the metal-catalyzed regioselective C-H functionalization of quinoline N-oxides at the 8-position: direct iodination and amidation were developed using rhodium and iridium catalytic systems, respectively. Mechanistic study of the amidation revealed that the unique regioselectivity is achieved through the smooth formation of N-oxide-chelated iridacycle and that an acid additive plays