20442-76-6Relevant academic research and scientific papers
Chiral Diarylmethanes via Copper-Catalyzed Asymmetric Allylic Arylation with Organolithium Compounds
Guduguntla, Sureshbabu,Hornillos, Valentín,Tessier, Romain,Fa?anás-Mastral, Martín,Feringa, Ben L.
, p. 252 - 255 (2016/02/03)
A highly enantioselective copper/N-heterocyclic carbene catalyzed allylic arylation with organolithium compounds is presented. The use of commercial or readily prepared aryllithium reagents in the reaction with allyl bromides affords a variety of chiral diarylvinylmethanes, comprising a privileged structural motif in pharmaceuticals, in high yields with good to excellent regio- and enantioselectivities. The versatility of this new transformation is illustrated in the formal synthesis of the marketed drug tolterodine (Detrol).
Flow chemistry as a discovery tool to access sp2-sp3 cross-coupling reactions via diazo compounds
Tran, Duc N.,Battilocchio, Claudio,Lou, Shing-Bong,Hawkins, Joel M.,Ley, Steven V.
, p. 1120 - 1125 (2015/03/04)
The work takes advantage of an important feature of flow chemistry, whereby the generation of a transient species (or reactive intermediate) can be followed by a transfer step into another chemical environment, before the intermediate is reacted with a coupling partner. This concept is successfully applied to achieve a room temperature sp2-sp3 cross coupling of boronic acids with diazo compounds, these latter species being generated from hydrazones under flow conditions using MnO2 as the oxidant.
FeCl3·6H2O-catalyzed selective reduction of allylic halides to alkenes with concomitant oxidation of benzylic alcohols to aldehydes
Zhang, Houcai,Liu, Ruiting,Zhou, Xigeng
, p. 282 - 288 (2014/03/21)
Iron-catalyzed direct reduction of allylic halides with benzylic alcohol was achieved, providing a new, simple, and efficient method for conducting highly regioselective hydrodehalogenation. This method not only features a readily available reductant, an
Catalytic asymmetric carbong-carbon bond formation via allylic alkylations with organolithium compounds
Perez, Manuel,Fananas-Mastral, Martin,Bos, Pieter H.,Rudolph, Alena,Harutyunyan, Syuzanna R.,Feringa, Ben L.
experimental part, p. 377 - 381 (2012/01/06)
Carbon-carbon bond formation is the basis for the biogenesis of nature's essential molecules. Consequently, it lies at the heart of the chemical sciences. Chiral catalysts have been developed for asymmetric C-C bond formation to yield single enantiomers from several organometallic reagents. Remarkably, for extremely reactive organolithium compounds, which are among the most broadly used reagents in chemical synthesis, a general catalytic methodology for enantioselective C-C formation has proven elusive, until now. Here, we report a copper-based chiral catalytic system that allows carbon-carbon bond formation via allylic alkylation with alkyllithium reagents, with extremely high enantioselectivities and able to tolerate several functional groups. We have found that both the solvent used and the structure of the active chiral catalyst are the most critical factors in achieving successful asymmetric catalysis with alkyllithium reagents. The active form of the chiral catalyst has been identified through spectroscopic studies as a diphosphine copper monoalkyl species.
An efficient 1,3-allylic carbonyl transposition of chalcones
Khurana, Jitender M.,Dawra, Kiran,Majumdar, Susruta
experimental part, p. 69 - 72 (2010/03/24)
A very simple, convenient, and efficient procedure is reported for the 1,3-allylic carbonyl transposition of chalcones. The transposition can be achieved by reduction of chalcones to 1,3-diarylpropan-1-ols and dehydration of the latter to give 1,3-diarylpropenes followed by benzylic/allylic oxidation.
Arylations of allylic acetates with triarylbismuths as atom-efficient multi-coupling reagents under palladium catalysis
Rao, Maddali L.N.,Banerjee, Debasis,Giri, Somnath
scheme or table, p. 5757 - 5761 (2009/12/24)
Arylation of allylic acetates employing triarylbismuths as multi-coupling reagents under palladium-catalyzed conditions was reported. Triarylbismuths as nucleophilic coupling partners were used in sub-stoichiometric amounts with respect to allylic acetate
Efficient chiral N-heterocyclic carbene/copper(I)-catalyzed asymmetric allylic arylation with aryl Grignard reagents
Selim, Khalid B.,Matsumoto, Yasumasa,Yamada, Ken-Ichi,Tomioka, Kiyoshi
scheme or table, p. 8733 - 8735 (2010/02/28)
Gamma rules: The title reaction was achieved in a highly regioselective manner using aryl Grignard reagents with monodentate chiral N-heterocyclic carbenel copper(I) catalyst to givediarylvinylmethanes with excellent enantiomeric excess in excellent yield
FeCl3 · 6H2O catalyzed disproportionation of allylic alcohols and selective allylic reduction of allylic alcohols and their derivatives with benzyl alcohol
Wang, Jialiang,Huang, Wen,Zhang, Zhengxing,Xiang, Xu,Liu, Ruiting,Zhou, Xigeng
supporting information; experimental part, p. 3299 - 3304 (2009/09/08)
Iron chloride has been found to be an efficient catalyst for the disproportionation of allylic alcohols, which provides a convenient method for selective transformation of allylic alcohols to alkenes and α,β- unsaturated ketones. Furthermore, this catalytic system is also effective for highly selective allylic reduction of allylic alcohols, allylic ethers, and allylic acetates with benzyl alcohol under neutral and convenient reaction conditions.
Enantioselective iridium-catalyzed allylic arylation
Polet, Damien,Rathgeb, Xavier,Falciola, Caroline A.,Langlois, Jean-Baptiste,El Hajjaji, Samir,Alexakis, Alexandre
supporting information; experimental part, p. 1205 - 1216 (2009/09/06)
We describe herein the development of the first iridium-catalyzed allylic substitution using arylzinc nucleophiles. High enantioselectivities were obtained from the reactions, which used commercially available Grignard reagents as the starting materials. This methodology was also shown to be compatible with halogen/metal exchange reactions. Its synthetic potential is demonstrated by its application towards the formal synthesis of (+)-sertraline.
Copper-catalyzed asymmetric allylic substitution with aryl and ethyl Grignard reagents
Selim, Khalid B.,Yamada, Ken-Ichi,Tomioka, Kiyoshi
supporting information; experimental part, p. 5140 - 5142 (2009/03/11)
Phenyl- and ethyl-magnesium bromides undergo regioselective asymmetric allylic substitution with high enantioselectivity under the catalysis of chiral amidophosphane-copper(i) complexes. The Royal Society of Chemistry.
