5912-82-3Relevant academic research and scientific papers
A new insight into the push-pull effect of substituents via the stilbene-like model compounds
Cao, Chaotun,Zeng, Zhao,Cao, Chenzhong
, (2022/02/01)
In this paper, authors report on 1-pyridyl-2-arylethenes, 1-furyl-2-arylethylenes, 1,2-diphenylpropylenes and substituted cinnamyl anilines as stilbene-like model compounds to investigate the factors dominating the push-pull effect of substituents via usi
Nickel-catalyzed Heck reaction of cycloalkenes using aryl sulfonates and pivalates
Zhou, Jianrong Steve,Huang, Xiaolei,Teng, Shenghan,Chi, Yonggui Robin
supporting information, p. 3933 - 3936 (2021/04/26)
Nickel-catalyzed Heck reaction of cycloalkenes delivers unusual conjugated arylated isomers. Nickel(0) catalysts ligated by chelating dialkylphosphines effectively activate not only aryl triflates as electrophiles, but also less reactive aryl mesylates, t
Cobalt(II)-Catalyzed Stereoselective Olefin Isomerization: Facile Access to Acyclic Trisubstituted Alkenes
Zhang, Sheng,Bedi, Deepika,Cheng, Lu,Unruh, Daniel K.,Li, Guigen,Findlater, Michael
supporting information, p. 8910 - 8917 (2020/12/23)
Stereoselective synthesis of trisubstituted alkenes is a long-standing challenge in organic chemistry, due to the small energy differences between E and Z isomers of trisubstituted alkenes (compared with 1,2-disubstituted alkenes). Transition metal-catalyzed isomerization of 1,1-disubstituted alkenes can serve as an alternative approach to trisubstituted alkenes, but it remains underdeveloped owing to issues relating to reaction efficiency and stereoselectivity. Here we show that a novel cobalt catalyst can overcome these challenges to provide an efficient and stereoselective access to a broad range of trisubstituted alkenes. This protocol is compatible with both mono- and dienes and exhibits a good functional group tolerance and scalability. Moreover, it has proven to be a useful tool to construct organic luminophores and a deuterated trisubstituted alkene. A preliminary study of the mechanism suggests that a cobalt-hydride pathway is involved in the reaction. The high stereoselectivity of the reaction is attributed to both a π-πstacking effect and the steric hindrance between substrate and catalyst.
Supported Au Nanoparticles-Catalyzed Regioselective Dehydrogenative Disilylation of Allenes by Dihydrosilane
Kidonakis, Marios,Kotzabasaki, Vasiliki,Vasilikogiannaki, Eleni,Stratakis, Manolis
, p. 9170 - 9173 (2019/07/12)
Supported Au nanoparticles on TiO2 catalyze the unprecedented dehydrogenative disilylation of monosubstituted and 1,1-disubstituted allenes by Et2SiH2 exclusively on the terminal double bond in a stereoselective manner. Tr
Dipalladium(I) complexes of ortho- and para-functionalized 1,3-bis(aryl)triazenide ligands: Synthesis, structure and catalytic activity
Correa-Ayala, Erick,Campos-Alvarado, Carlos,Chávez, Daniel,Hernández-Ortega, Simón,Morales-Morales, David,Miranda-Soto, Valentín,Parra-Hake, Miguel
, p. 130 - 138 (2019/03/12)
The synthesis and characterization of a series dipalladium(I) complexes of formulae [Pd{1-[2′-(methoxycarbonyl)phenyl]-3-[4′-X-phenyl]triazenide}]2 [X = F (4), Cl (5), Br (6)] are reported. The crystal structure of complex 4 was determined by X-ray diffraction studies. The previously reported dipalladium(I) 1–3 as well as the new complexes 4–6 were used as catalysts in the Heck and Suzuki couplings of different p-substituted bromobenzenes.
Iodine-catalyzed transformation of aryl-substituted alcohols under solvent-free and highly concentrated reaction conditions
Jereb, Marjan,Vra?i?, Dejan
, p. 747 - 762 (2018/01/17)
Iodine-catalyzed transformations of alcohols under solvent-free reaction conditions (SFRC) and under highly concentrated reaction conditions (HCRC) in the presence of various solvents were studied in order to gain insight into the behavior of the reaction intermediates under these conditions. Dimerization, dehydration and substitution were the three types of transformations observed with benzylic alcohols. Dimerization and substitution reactions were predominant in the case of primary- and secondary alcohols, whereas dehydration prevailed in the case of tertiary alcohols. The relative reactivity of substituted 1-phenylethanols in I2-catalyzed dimerization under SFRC provided a good Hammett plot ρ+ = -2.8 (r2 = 0.98), suggesting the presence of electron-deficient intermediates with a certain degree of developed charge in the rate-determining step.
Intramolecular 10,10a-[2+2] photocycloaddition reactions of phenanthrenes with linked styrene
Maeda, Hajime,Nakashima, Ryota,Sugimoto, Akira,Mizuno, Kazuhiko
, p. 232 - 237 (2016/07/21)
Intramolecular photocycloaddition reactions of styrene linked 9-cyanophenanthrenes led to formation of C-9 C-10 [2+2] cycloadducts which underwent cycloreversion under the prolonged irradiation conditions to regenerate the starting substrates. Unusual 8-membered ring products were irreversibly formed in these processes. Product distributions were governed by substituent controlled, donor-acceptor interactions that direct generation of two intramolecular singlet exciplexes, which serve as intermediates in the pathways to formation of 9,10- and 10,10a-[2+2] adducts.
Chloride-Bridged Dinuclear Rhodium(III) Complexes Bearing Chiral Diphosphine Ligands: Catalyst Precursors for Asymmetric Hydrogenation of Simple Olefins
Kita, Yusuke,Hida, Shoji,Higashihara, Kenya,Jena, Himanshu Sekhar,Higashida, Kosuke,Mashima, Kazushi
supporting information, p. 8299 - 8303 (2016/07/19)
Efficient rhodium(III) catalysts were developed for asymmetric hydrogenation of simple olefins. A new series of chloride-bridged dinuclear rhodium(III) complexes 1 were synthesized from the rhodium(I) precursor [RhCl(cod)]2, chiral diphosphine ligands, and hydrochloric acid. Complexes from the series acted as efficient catalysts for asymmetric hydrogenation of (E)-prop-1-ene-1,2-diyldibenzene and its derivatives without any directing groups, in sharp contrast to widely used rhodium(I) catalytic systems that require a directing group for high enantioselectivity. The catalytic system was applied to asymmetric hydrogenation of allylic alcohols, alkenylboranes, and unsaturated cyclic sulfones. Control experiments support the superiority of dinuclear rhodium(III) complexes 1 over typical rhodium(I) catalytic systems.
Al(OTf)3: An efficient lewis acid additive for domino addition-elimination of Grignard reagents to activated ketones
Pieterse, Tanya,Visser, Melanie,Marais, Charlene,Bezuidenhoudt, Barend C. B.
supporting information, p. 1541 - 1546 (2016/06/14)
It has been demonstrated that aluminium triflate in either stoichiometric or catalytic quantities facilitates the addition-elimination of Grignard reagents to electron-rich ketones, such as methoxy substituted acetophenones, propiophenone and chromanone in a one-pot process, and that it has an enhancing effect on the addition of these reagents to the ketones. It has also been found that the reactions are highly stereoselective towards one regioisomer of the alkene in the case of oxygenated aryl-alkyl substituted substrates, but not when the elimination originates from a double benzylic alcohol intermediate.
MIDA-Vinylsilanes: Selective Cross-Couplings and Applications to the Synthesis of Functionalized Stilbenes
McLaughlin, Mark G.,McAdam, Catherine A.,Cook, Matthew J.
supporting information, p. 10 - 13 (2015/07/28)
(Chemical Equation Presented). A rapid and stereodefined synthesis of MIDA-boryl vinylsilanes has been achieved through the hydrosilylation of an alkynylboronic ester. The E products which contain a silyl and boryl group can be selectively cross-coupled i
