3262-39-3Relevant academic research and scientific papers
Photo-induced oxidative cleavage of C-C double bonds of olefins in water
Zhang, Yilan,Yue, Xiaoguang,Liang, Chenfeng,Zhao, Jianming,Yu, Wenbo,Zhang, Pengfei
supporting information, (2021/08/27)
The carbonyl compounds, synthesized by the oxidative cleavage of their corresponding olefins, are of great significance in organic synthesis, especially aryl ketones. We have developed a gentle and effective protocol, using acid red 94 as the organic metal-free photocatalyst, O2 as the oxidant, and water as the solvent. Under visible light irradiation, aryl ketone derivatives were obtained in moderate to excellent yields, showing good economic and environmental advantages.
Porous organic polymer supported rhodium as a heterogeneous catalyst for hydroformylation of alkynes to α,β-unsaturated aldehydes
Liang, Zuyu,Chen, Jianbin,Chen, Xin,Zhang, Kai,Lv, Jinhe,Zhao, Haowen,Zhang, Guoying,Xie, Congxia,Zong, Lingbo,Jia, Xiaofei
, p. 13721 - 13724 (2019/11/19)
A new porous organic polymer supported rhodium catalyst (Rh/POL-BINAPa&PPh3) has been developed for the hydroformylation of various alkynes to afford the corresponding α,β-unsaturated aldehydes with high chem- and stereoselectivity, excellent catalytic activity and good reusability (10 cycles). The heterogeneous catalyst exhibited more catalytic activity than the comparable homogeneous Rh/BINAPa/PPh3 system.
Selective rhodium-catalyzed hydroformylation of alkynes to α,β-unsaturated aldehydes with a tetraphosphoramidite ligand
Zhang, Zongpeng,Wang, Qian,Chen, Caiyou,Han, Zhengyu,Dong, Xiu-Qin,Zhang, Xumu
supporting information, p. 3290 - 3293 (2016/07/13)
A tetraphosphoramidite ligand was successfully applied to a Rh-catalyzed hydroformylation of various symmetrical and unsymmetrical alkynes to afford corresponding α,β-unsaturated aldehyde products in good to excellent yields (up to 97% yield). Excellent chemo- and regioselectivities and high activities (up to 20 000 TON) were achieved. The corresponding α,β-unsaturated aldehyde products can be transformed into many useful and important organic molecules, such as indenamine derivatives and lukianol pyrroles. This great performance makes the hydroformylation of alkynes highly practical with great potential.
Assisted tandem catalytic cross metathesis-oxidation: In one flask from styrenes to 1,2-diketones and further to quinoxalines
Schmidt, Bernd,Krehl, Stefan,Hauke, Sylvia
, p. 5427 - 5435 (2013/07/25)
1,2-Diketones were synthesized from styrenes by combining a cross metathesis and a Ru-catalyzed alkene oxidation to an assisted tandem catalytic sequence. The synthesis relies on the use of just one metathesis precatalyst, which was in situ converted to the oxidation catalyst by addition of an alkyl hydroperoxide as a chemical trigger and oxidant. The one-flask sequence can be extended beyond 1,2-diketones to quinoxalines, by condensation of the oxidation products with ortho-phenylenediamine.
Dehalogenation of organic halides by flash vacuum pyrolysis over magnesium: A versatile synthetic method
Aitken, R. Alan,Hodgson, Philip K. G.,Oyewale, Adebayo O.,Morrison, John J.
, p. 1163 - 1164 (2007/10/03)
Flash vacuum pyrolysis over magnesium at 600°C results in efficient dehalogenation of a variety of organic halides and provides a preparatively useful method for C-C bond formation and other reactions.
Substituent Effect Studies of Aryl-Assisted Solvolyses. I. The Acetolysis of 2,2-Bis(substituted phenyl)ethyl p-Toluenesulfonates
Fujio, Mizue,Maeda, Yasuyuki,Goto, Mutsuo,Saeki, Yoshihiro,Mishima, Masaaki,Tsuno, Yuho
, p. 3015 - 3020 (2007/10/02)
The substituent effect on the acetolysis of 2,2-bis(substituted phenyl)ethyl p-toluenesulfonates at 90.10 deg C can be described accurately in terms of the Yukawa-Tsuno (LArSR) relationship, giving a ρ value of -4.44 and an r value of 0.53. The substituent effect correlation of this system carrying two aryls is quite comparable to that of the 2-methyl-2-phenylpropyl system carrying a single aryl group, suggesting the close similarity in the structure of the transition states between the systems. The results can be reasonably accounted for on the basis of the accepted mechanism of this reaction, involving a rate-determining aryl-assisted transition state where only one aryl group of the two β-aryl groups participates.
Spatial Structure of 4n? Helicene Dianions
Frim, R.,Goldblum, A.,Rabinovitz, M.
, p. 267 - 274 (2007/10/02)
Helicene dianions, e.g. phenanthrene derivatives, once believed to be non-helical, maintain their chirality as 4n? dianions.Phenanthrene 5, as well as substituted phenanthrene derivatives, undergo a two-electron reduction to form the respective 4n? dianion e.g. 52-/2Li+.Phenanthrene derivatives substituted at the 4- and 5-positions (bay substituents) e.g. 6-11, which are helical, afford stable dianions.These dianions are also prepared by a two-electron reduction of the (4n+2)? electron hydrocarbons and show, in their 1H NMR spectra, a quench of the paratropicity compared to 52- as well as a line shape dependence on their twist angle.The quench of paratropicity was also observed in the closely related charged helicenes derived from the benzochrysene system, i.e. anions 122- and 132-.The twist angles were calculated by MMX and MNDO calculations for the neutral systems, i.e., 5-11, and by MNDO for the dianions.MNDO calculations also included the preferred location of the counter cation.A dynamic NMR spectroscopic study proves experimentally the helicity of anion 112- thus shedding light on the behaviour of this novel class of dianions.
New Three- and Sixfold Bridged Phenylogous Cyclophanes
Sendhoff, Norbert,Kissener, Wolfram,Voegtle, Fritz,Franken, Sybille,Puff, Heinrich
, p. 2179 - 2186 (2007/10/02)
The syntheses of the threefold bridged cyclophanes 4, 5, of the sixfold bridged cyclophane 6, and of the triple-layered cyclophanes 7, 8 are reported.The yields have been optimized by variation of the reaction conditions and by use of the cesium effect.The enantiomer resolution of 7 and the X-ray structural analysis of 4 are discussed.
RHODIUM ION CATALYZED DECOMPOSITION OF ARYLDIAZOALKANES
Shankar, B.K. Ravi,Shechter, Harold
, p. 2277 - 2280 (2007/10/02)
Aryldiazomethanes are converted by rhodium(II)acetate and iodorhodium(III) tetraphenylporphyrin to cis- rather than trans-1,2-diarylethylenes.Secondary aryldiazoalkanes react with rhodium(II) acetate to give azines.
