14134-06-6Relevant academic research and scientific papers
1H and 13C Nuclear Magnetic Resonance Studies of Ethenyl-Substituted Benzenoid Aromatic Compounds
Katritzky, Alan R.,Hitchings, Gregory J.,King, Roy W.,Zhu, Dong W.
, p. 2 - 8 (1991)
1H and 13C NMR studies were carried out on 1-ethenylnaphthalene, 2-ethenylnaphthalene, 9-ethenylanthracene, 9-ethenylphenanthrene, 1-ethenylpyrene and 1-ethenylperylene.Assignments of proton and carbon resonances were made with the aid of 2D COSY, 2D COLOC, 2D COLOCS, 3J(H,C) INAPT, and NOE difference spectral techniques.
Oxocarbons and related compounds. Part 28. Polycycle-fused dihydrobenzocyclobutenediones and benzocyclobutenediones. Synthesis of cyclobuta[c]- and cyclobuta[a]-phenanthrene-1,2-diones and cyclobuta[a]triphenylene-11,12-dione
Schmidt, Arthur H.,Kircher, Gunnar,Zylla, Joerg,Veit, Stephan
, p. 409 - 414 (1999)
The Diels-Alder reaction of semisquaric chloride 5 with 1-(alk-1-enyl)naphthalenes, 2-(alk-1-enyl)naphthalenes and 9-vinylphenanthrene is used to prepare dihydrocyclobuta[c]phenanthrene-1,2-diones 8a-c, dihydrocyclobuta[a]phenanthrene-1,2-diones 12a-c, and dihydrocyclobuta[a]triphenylene-11,12-dione 18, respectively. Treatment of the dihydrocyclobutaarenediones with bromine effects aromatization and opens up a route for the synthesis of cyclobuta[c]phenanthrene-1,2-diones 9a-c, cyclobuta[a]phenanthrene-1,2-diones 13a-c and cyclobuta[a]triphenylene-11,12-dione 19. The range of Diels-Alder reactions with semisquaric chloride 5 is extended to the use of 4-(prop-1-enyl)-1,2-dihydronaphthalene 14. Tetrahydrocyclobuta[a]phenanthrene-1,2-dione 15 is obtained in 69% yield, which can be oxidized, stepwise or at once, to give cyclobuta[a]phenanthrene-1,2-dione 13b in good yields.
A novel bis-Lactonisation of naphtho- and phenanthro-1,2-dioxines with malonate nucleophiles
Greatrex, Ben,Jevric, Martyn,Kimber, Marc C.,Krivickas, Sara J.,Taylor, Dennis K.,Tiekink, Edward R. T.
, p. 668 - 672 (2003)
Malonate nucleophiles add in a conjugate fashion to substituted naphtho- and phenanthro-1,2-dioxines to furnish functionalised bis-lactones in high yield and with high de. The basicity of the malonate nucleophile is sufficiently mild to rearrange the 1,2-dioxines to yield the transient cis-δhydroxy enone species with no further Kornblum-DeLaMare rearrangement. The cis-δhydroxy enones readily undergo conjugate addition by malonate nucleophiles in a highly diastereoselective fashion. An intramolecular domino cyclisation then ensues yielding the observed bis-lactones. The relative configuration of the bis-lactone series was established by 1- and 2-D 1H, 13C NMR techniques and further confirmed by single crystal X-ray analysis.
Copper-Catalyzed Intermolecular Enantioselective Radical Oxidative C(sp3)?H/C(sp)?H Cross-Coupling with Rationally Designed Oxazoline-Derived N,N,P(O)-Ligands
Gu, Qiang-Shuai,Guo, Kai-Xin,Li, Zhong-Liang,Liu, Lin,Liu, Xin-Yuan,Tian, Yu,Yang, Chang-Jiang,Ye, Liu
supporting information, p. 26710 - 26717 (2021/11/18)
The intermolecular asymmetric radical oxidative C(sp3)?C(sp) cross-coupling of C(sp3)?H bonds with readily available terminal alkynes is a promising method to forge chiral C(sp3)?C(sp) bonds because of the high atom and step economy, but remains underexplored. Here, we report a copper-catalyzed asymmetric C(sp3)?C(sp) cross-coupling of (hetero)benzylic and (cyclic)allylic C?H bonds with terminal alkynes that occurs with high to excellent enantioselectivity. Critical to the success is the rational design of chiral oxazoline-derived N,N,P(O)-ligands that not only tolerate the strong oxidative conditions which are requisite for intermolecular hydrogen atom abstraction (HAA) processes but also induce the challenging enantiocontrol. Direct access to a range of synthetically useful chiral benzylic alkynes and 1,4-enynes, high site-selectivity among similar C(sp3)?H bonds, and facile synthesis of enantioenriched medicinally relevant compounds make this approach very attractive.
Hollow Carbon Sphere Nanoreactors Loaded with PdCu Nanoparticles: Void-Confinement Effects in Liquid-Phase Hydrogenations
Dong, Chao,Liu, Jian,Su, Panpan,Wang, Guang-Hui,Ye, Run-Ping,Yu, Qun
supporting information, p. 18374 - 18379 (2020/08/19)
Nanoreactors with hollow structures have attracted great interest in catalysis research due to their void-confinement effects. However, the challenge in unambiguously unraveling these confinement effects is to decouple them from other factors affecting catalysis. Here, we synthesize a pair of hollow carbon sphere (HCS) nanoreactors with presynthesized PdCu nanoparticles encapsulated inside of HCS (PdCu?HCS) and supported outside of HCS (PdCu/HCS), respectively, while keeping other structural features the same. Based on the two comparative nanoreactors, void-confinement effects in liquid-phase hydrogenation are investigated in a two-chamber reactor. It is found that hydrogenations over PdCu?HCS are shape-selective catalysis, can be accelerated (accumulation of reactants), decelerated (mass transfer limitation), and even inhibited (molecular-sieving effect); conversion of the intermediate in the void space can be further promoted. Using this principle, a specific imine is selectively produced. This work provides a proof of concept for fundamental catalytic action of the hollow nanoreactors.
Method for efficiently preparing styrene and deuterated styrene compounds
-
Paragraph 0120-0123, (2020/09/12)
The invention discloses a method for efficiently preparing a styrene compound and a deuterated styrene compound. A phenylacetylene compound and water or heavy water are used as reaction raw materials;lewis acid is used as a catalyst; reacting and synthesizing in an organic solvent under a reducing agent are carried out to obtain a target product styrene compound or deuterated styrene compound; the reaction general formula is disclosed in the invention; the invention provides a method for preparing the styrene compound and the deuterated styrene compound, which is simple, mild, efficient and green to operate; water or heavy water is taken as a hydrogen source and a deuterium source respectively, and the process is green and environment-friendly; in addition, the method is simple and easy to operate, mild in reaction condition and high in synthesis efficiency, the yield of styrene reaches up to 99%, the yield of deuterated styrene reaches up to 99%, the deuterium doping rate reaches upto 98% (alpha) and 96% (beta), and wide application prospects are achieved.
Pd-Catalyzed Synthesis of Vinyl Arenes from Aryl Halides and Acrylic Acid
Gao, Yang,Ou, Yang,Goo?en, Lukas J.
supporting information, p. 8709 - 8712 (2019/06/17)
Acrylic acid is presented as an inexpensive, non-volatile vinylating agent in a palladium-catalyzed decarboxylative vinylation of aryl halides. The reaction proceeds through a Heck reaction of acrylic acid, immediately followed by protodecarboxylation of the cinnamic acid intermediate. The use of the carboxylate group as a deciduous directing group ensures high selectivity for monoarylated products. The vinylation process is generally applicable to diversely substituted substrates. Its utility is shown by the synthesis of drug-like molecules and the gram-scale preparation of key intermediates in drug synthesis.
PdCx nanocrystals with tunable compositions for alkyne semihydrogenation
Guo, Ruiyun,Chen, Qiang,Li, Xiang,Liu, Yaming,Wang, Chaoqi,Bi, Wei,Zhao, Caiyang,Guo, Yanjun,Jin, Mingshang
supporting information, p. 4714 - 4720 (2019/03/07)
The palladium carbide (PdCx) material has shown great promise as an efficient catalyst for alkyne semihydrogenation. Difficulties in preparing stable PdCx catalysts have been recognized as the main obstacle. Here, we synthesized a highly stable and durable class of PdCx nanocrystals by treating pre-formed Pd nanocrystals with glucose under hydrothermal conditions. The C/Pd atomic ratios in the resultant PdCx nanocrystals can be varied from 0.04 to 0.18, simply by changing the reaction time. The catalytic results for semihydrogenation of 4-ethynyl-1,1′-biphenyl show that PdC0.18 nanocrystals exhibit an activity with a turnover frequency as high as 7896 h-1, ～7.6 and ～38 times higher than that of commercial Pd/C and Lindlar catalysts, respectively, as well as a selectivity of >99%.
Direct trans-Selective Ruthenium-Catalyzed Reduction of Alkynes in Two-Chamber Reactors and Continuous Flow
Neumann, Karoline T.,Klimczyk, Sebastian,Burhardt, Mia N.,Bang-Andersen, Benny,Skrydstrup, Troels,Lindhardt, Anders T.
, p. 4710 - 4714 (2016/07/12)
An efficient trans-selective hydrogenation of alkynes under low hydrogen pressure and low reaction temperatures is reported, applying a commercially available ruthenium hydride complex. The developed reaction conditions, which tolerate a variety of functional groups, are carried out in a two-chamber setup with ex situ generated hydrogen. The reaction setup is highly suitable for deuterium labeling. The trans-selective hydrogenation was extrapolated to a transfer hydrogenation protocol, employing a packed bed immobilized ruthenium hydride catalyst in continuous flow with a retention time of only 10 min.
KOt-Bu/DMF promoted intramolecular cyclization of 1,1′-biphenyl aldehydes and ketones: An efficient synthesis of phenanthrenes
Chen, Yan-Yan,Zhang, Niu-Niu,Ye, Lin-Miao,Chen, Jia-Hua,Sun, Xiang,Zhang, Xue-Jing,Yan, Ming
, p. 48046 - 48049 (2015/06/16)
A new synthesis of phenanthrene derivatives has been achieved through intramolecular cyclization of 1,1′-biphenyl aldehydes and ketones promoted by KOt-Bu/DMF. A free radical reaction pathway is proposed.
