35030-49-0Relevant academic research and scientific papers
On the mechanism of conversion of 4-carboxy-3,4-dihydro-3-phenyl-1(2H)-isoquinolones to indeno[1,2-c]isoquinolines by thionyl chloride
Xiao, Xiangshu,Morrell, Andrew,Fanwick, Phillip E.,Cushman, Mark
, p. 9705 - 9712 (2006)
It has been known for a long time that thionyl chloride can effectively mediate the transformation of 4-carboxy-3,4-dihydro-3-phenyl-1(2H)-isoquinolones to indeno[1,2-c]isoquinolines. The mechanism of this unique transformation, however, remains to be established. Evidence is presented to demonstrate that (1) the two-electron dehydrogenation precedes Friedel-Crafts cyclization and (2) the two-electron dehydrogenation occurs via H-4 deprotonation and subsequent O-sulfinylation of the lactam moiety instead of C-sulfinylation of the carbon α to the carboxyl group.
Asymmetric Aminations and Kinetic Resolution of Acyclic α-Branched Ynones
He, Faqian,Shen, Guosong,Yang, Xiaoyu
supporting information, p. 15 - 20 (2021/11/20)
An efficient method for asymmetric synthesis of acyclic α-tertiary amine derivatives has been achieved through enantioselective aminations of α-branched ynones with azodicarboxylates enabled by chiral phosphoric acid catalysis. Moreover, kinetic resolution of racemic starting material was realized under these conditions, which gave access to valuable enantioenriched α-substituted ketones. A wide array of α-aryl and alkyl-substitutions, and the substituted alkynyl groups were well compatible with this method, producing both the amination products and the recovered ketones with good to high enantioselectivities.
Transition-metal-free and base promoted C-C bond formationviaC-N bond cleavage of organoammonium salts
Chen, Tieqiao,Huang, Tianzeng,Ke, Yuting,Li, Chunya,Liu, Long,Tang, Yuanyuan,Tang, Zhi,Wang, Kunyu,Zhang, Tao
supporting information, p. 8237 - 8240 (2021/10/12)
A transition-metal-free and base promoted C-C bond forming reaction of benzyl C(sp3)-H bond with organoammonium saltsviaC-N bond cleavage has been reported. Benzyl ammonium salts as well as cinnamyl ammonium salt could couple readily with various benzyl C(sp3)-H species, producing the corresponding products in moderate to excellent yields with good functional group tolerance. Late stage chemical manipulation enabled the specific 1,2-diarylethane structure of products transformed into useful olefin compoundsviadehydrogenation, which further demonstrated the utility of this reaction.
Copper and palladium co-catalyzed highly regio-selective 1,2-hydroarylation of terminal 1,3-dienes
Zhang, Rumeng,Li, Qifan,Zhang, Min,Chai, Sida,Duan, Yuqi,Su, Jingfei,Zhao, Qian,Zhang, Chun
, p. 13551 - 13554 (2020/11/17)
A practical copper and palladium co-catalyzed highly regio-selective hydroarylation of terminal 1,3-dienes has been developed. This chemistry afforded the terminal alkenyl group containing products, which are a kind of versatile precursor for organic synthesis, from 1,3-dienes by a practical one-step reaction. With good functional group tolerance, this protocol could be used to make a series of bio-active compounds using readily accessible starting materials. The mechanism of this reaction was explored by control experiments and kinetics studies. This journal is
Formation of quaternary carbons through cobalt-catalyzed C(sp3)-C(sp3) Negishi cross-coupling
Palao, Eduardo,López, Enol,Torres-Moya, Iván,De La Hoz, Antonio,Díaz-Ortiz, ángel,Alcázar, Jesús
, p. 8210 - 8213 (2020/08/17)
Formation of all-carbon-substituted quaternary carbons is a key challenge in organic and medicinal chemistry. We report a cobalt-catalyzed C(sp3)-C(sp3) cross-coupling that allows for the introduction of benzyl, heteroarylmethylzinc and allyl groups to halo-carbonyl substrates. The cross-coupling reaction is selective for C(sp3)-over C(sp2)-halides, in contrast to most used catalytic metals, and allows access to novel scaffolds of pharmaceutical interest. NMR mechanistic studies suggest the presence of Co(0) complexes as catalytic species. This journal is
Harnessing Applied Potential: Selective β-Hydrocarboxylation of Substituted Olefins
Alkayal, Anas,Buckley, Benjamin R.,Malkov, Andrei V.,Montanaro, Stephanie,Tabas, Volodymyr,Wright, Iain A.
, (2020/02/13)
The construction of carboxylic acid compounds in a selective fashion from low value materials such as alkenes remains a long-standing challenge to synthetic chemists. In particular, β-addition to styrenes is underdeveloped. Herein we report a new electrosynthetic approach to the selective hydrocarboxylation of alkenes that overcomes the limitations of current transition metal and photochemical approaches. The reported method allows unprecedented direct access to carboxylic acids derived from β,β-trisubstituted alkenes, in a highly regioselective manner.
A general platinum-catalyzed alkoxycarbonylation of olefins
Beller, Matthias,Dühren, Ricarda,Franke, Robert,Ge, Yao,Huang, Weiheng,Jackstell, Ralf,Liu, Jiawang,Neumann, Helfried,Schneider, Carolin,Yang, Ji
supporting information, p. 5235 - 5238 (2020/07/30)
Hydroxy- and alkoxycarbonylation reactions constitute important industrial processes in homogeneous catalysis. Nowadays, palladium complexes constitute state-of-the-art catalysts for these transformations. Herein, we report the first efficient platinum-catalysed alkoxycarbonylations of olefins including sterically hindered and functionalized ones. This atom-efficient catalytic transformation provides straightforward access to a variety of valuable esters in good to excellent yields and often with high selectivities. In kinetic experiments the activities of Pd- and Pt-based catalysts were compared. Even at low catalyst loading, Pt shows high catalytic activity.
Palladium-catalyzed α,β-dehydrogenation of acyclic ester equivalents promoted by a novel electron deficient phosphinooxazoline ligand
Fulton, Tyler J.,Wu, Brenda,Alexy, Eric J.,Zhang, Haiming,Stoltz, Brian M.
supporting information, p. 4104 - 4109 (2019/06/20)
A unique example of Pd-catalyzed decarboxylative dehydrogenation of fully substituted N-acyl allyl enol carbonates is enabled by a new electron deficient phosphinooxazoline (PHOX) ligand. The reaction proceeds from the Z-enol carbonate to provide dehydrogenation products exclusively in high E/Z selectivity, while the E-enol carbonate provides the α-allylation product with only minor dehydrogenation. The reaction proceeds with a broad scope of Z-enol carbonates derived from N-acyl indoles to furnish acyclic formal α,β-unsaturated ester equivalents.
Transition metal-free direct dehydrogenative arylation of activated C(sp3)-H bonds: Synthetic ambit and DFT reactivity predictions
Lovato, Kaitlyn,Guo, Lirong,Xu, Qing-Long,Liu, Fengting,Yousufuddin, Muhammed,Ess, Daniel H.,Kürti, László,Gao, Hongyin
, p. 7992 - 7999 (2018/11/03)
A transition metal-free dehydrogenative method for the direct mono-arylation of a wide range of activated C(sp3)-H bonds has been developed. This operationally simple and environmentally friendly aerobic arylation uses tert-BuOK as the base and nitroarenes as electrophiles to prepare up to gram quantities of structurally diverse sets (>60 examples) of α-arylated esters, amides, nitriles, sulfones and triaryl methanes. DFT calculations provided a predictive model, which states that substrates containing a C(sp3)-H bond with a sufficiently low pKa value should readily undergo arylation. The DFT prediction was confirmed through experimental testing of nearly a dozen substrates containing activated C(sp3)-H bonds. This arylation method was also used in a one-pot protocol to synthesize over twenty compounds containing all-carbon quaternary centers.
Palladium-catalyzed selective generation of CO from formic acid for carbonylation of alkenes
Sang, Rui,Kucmierczyk, Peter,Dong, Kaiwu,Franke, Robert,Neumann, Helfried,Jackstell, Ralf,Beller, Matthias
supporting information, p. 5217 - 5223 (2018/04/24)
A general and selective palladium-catalyzed alkoxycarbonylation of all kinds of alkenes with formic acid (HCOOH, FA) is described. Terminal, di-, tri-, and tetra-substituted including functionalized olefins are converted into linear esters with high yields and regioselectivity. Key-to-success is the use of specific palladium catalysts containing ligands with built-in base, e.g., L5. Comparison experiments demonstrate that the active catalyst system not only facilitates isomerization and carbonylation of alkenes but also promotes the selective decomposition of HCOOH to CO under mild conditions.
