3213-50-1Relevant academic research and scientific papers
Photo-induced anti-Markovnikov hydroalkylation of unactivated alkenes employing a dual-component initiator
Zhang, Yachao,Mao, Liang-Liang,Hu, Sifan,Luan, Yi,Cong, Huan
, p. 681 - 684 (2021)
Metal-free anti-Markovnikov hydroalkylation of unactivated alkenes with cyanoacetate has been developed, featuring the use of a dual-component initiator containing an organic photocatalyst and a radical precursor. When combined, the two components can und
Overcoming Selectivity Issues in Reversible Catalysis: A Transfer Hydrocyanation Exhibiting High Kinetic Control
Bhawal, Benjamin N.,Ehinger, Christian,Morandi, Bill,Reisenbauer, Julia C.
, p. 10914 - 10920 (2020/07/13)
Reversible catalytic reactions operate under thermodynamic control, and thus, establishing a selective catalytic system poses a considerable challenge. Herein, we report a reversible transfer hydrocyanation protocol that exhibits high selectivity for the thermodynamically less favorable branched isomer. Selectivity is achieved by exploiting the lower barrier for C-CN oxidative addition and reductive elimination at benzylic positions in the absence of a cocatalytic Lewis acid. Through the design of a novel type of HCN donor, a practical, branched-selective, HCN-free transfer hydrocyanation was realized. The synthetically useful resolution of a mixture of branched and linear nitrile isomers was also demonstrated to underline the value of reversible and selective transfer reactions. In a broader context, this work demonstrates that high kinetic selectivity can be achieved in reversible transfer reactions, thus opening new horizons for their synthetic applications.
AlCl3 catalyzed coupling of: N-benzylic sulfonamides with 2-substituted cyanoacetates through carbon-nitrogen bond cleavage
Hu, Chen,Hong, Gang,Qian, Xiaofei,Kim, Kwang Rim,Zhu, Xiaoyan,Wang, Limin
supporting information, p. 4984 - 4991 (2017/07/10)
A new cross-coupling reaction of N-benzylic sulfonamides with 2-substituted cyanoacetates for the synthesis of 2-substituted benzylbenzene was reported. In the presence of AlCl3, a broad range of N-benzylic sulfonamides reacted smoothly with 2-substituted cyanoacetates to afford structurally diverse benzylbenzenes in moderate to excellent yields. The conversion could be enlarged to gram-scale efficiently. The practicability of this approach was further manifested in the synthesis of a related bioactive agent with high anti-inflammatory activity.
Room Temperature, Reductive Alkylation of Activated Methylene Compounds: Carbon-Carbon Bond Formation Driven by the Rhodium-Catalyzed Water-Gas Shift Reaction
Denmark, Scott E.,Ibrahim, Malek Y. S.,Ambrosi, Andrea
, p. 613 - 630 (2017/06/05)
The rhodium-catalyzed water-gas shift reaction has been demonstrated to drive the reductive alkylation of several classes of activated methylene compounds at room temperature. Under catalysis by rhodium trichloride (2-3 mol %), carbon monoxide (10 bar), water (2-50 equiv), and triethylamine (2.5-7 equiv), the scope has been successfully expanded to cover a wide range of alkylating agents, including aliphatic and aromatic aldehydes, as well as cyclic ketones, in moderate to high yields. This method is comparable to, and for certain aspects, surpasses the established reductive alkylation protocols.
COMPOUNDS USEFUL AS MODULATORS OF TRPM8
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Paragraph 0469, (2016/03/29)
The present invention includes compounds useful as modulators of TRPM8, such as compounds of Formulae (Ia), (Ib) and (Ic), and the subgenus and species thereof; personal products containing those compounds; and the use of those compounds and the personal products, particularly the use of increasing or inducing chemesthetic sensations, such as cooling or cold sensations.
Development of pharmaceutical drugs, drug intermediates and ingredients by using direct organo-click reactions
Ramachary, Dhevalapally B.,Kishor, Mamillapalli,Reddy, Y. Vijayendar
supporting information; experimental part, p. 975 - 993 (2009/04/11)
Here we report on our studies of the use of combinations of amino acids, amines, K2CO3 or Cs2CO3 and CuSO4/Cu for catalysing green cascade reactions. We aimed to prepare the highly reactive and substituted olefin species 7 and 8, under very mild and environmentally friendly conditions, thus giving the hydrogenated products 10 and 12 through the action of Hantzsch ester (4) by self-catalysis through decreasing the HOMO-LUMO energy gaps between olefins 7/8 and Hantzsch ester (4) through biomimetic reductions. Highly useful compounds 10 to 14 were assembled from simple substrates such as aldehydes 1, ketones 2, CH acids 3, Hantzsch ester (4) and alkyl halides 5 by diversity-oriented green synthesis involving cascade olefination/hydrogenation (O/H), olefination/hydrogenation/alkylation (O/H/A) and hydrogenation/olefination/hydrogenation (H/O/H) reaction sequences in one-pot fashion with stereospecific organo- and organo-/metal-carbonate catalysis. Highly functionalized diverse compounds such as 10 to 14 are biologically active products and have found wide applications as pharmaceutical drugs, drug intermediates and drug ingredients. For the first time in organocatalysis, we report the O/H/A/TE reaction to furnish high yields of transesterification products 11 by simply mixing the reactants under proline/K2CO3 catalysis conditions. Additionally, a novel organocatalytic H/O/H reaction sequence for the synthesis of alkyl-substituted aromatics has been developed. Furthermore, for the first time we have developed organocatalysed cascade olefination/hydrogenation/hydrolysis (O/H/H) reactions to furnish highly useful materials such as 2-oxochroman-3-carboxylic acid (14kc) and 2-amino-4H-chromene-3-carbonitrile (14kj) in good yields. Experimentally simple and environmentally friendly organocatalytic two-carbon homologation through cascade O/H/H reactions of aldehydes 1, Meldrum's acid (3c), Hantzsch ester (4) and acetic acid/triethylamine in ethanol has been demonstrated. Additionally, we have developed a green synthesis of the highly substituted 1,2,3-triazole 17 from simple substrates through a two-step combination of olefination/hydrogenation/alkylation and Huisgen cycloaddition reaction sequences under stereospecific organocopper catalysis conditions. In this paper we have found strong support for our hypothesis that, "decreasing the HOMO-LUMO energy gap between olefins 7/8 and Hantzsch ester (4) will drive the biomimetic hydrogenation reaction by self-catalysis". This self-catalysis was further confirmed with many varieties of examples. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
Development of drug intermediates by using direct organocatalytic multi-component reactions
Ramachary, Dhevalapally B.,Kishor,Reddy, G. Babul
, p. 1641 - 1646 (2008/02/03)
Development of drug intermediates by using direct amino acid organocatalytic multi-component reaction was investigated. Hydrogenations of double-bond containing compounds including carbonyls, imines and olefins are important for living organisms as well as for the industrial production of chemicals. Amino acid catalysis has emerged as a powerful green synthetic tool for the development of both achiral and chiral catalysis of condensations and cycloadditions and the 1,2- and 1,4-additions of enals, enones and ketones including electrophiles. It was found that the amino acid proline 4a catalyzes the Knoevenagel condenstion of cyclohexanone 1a with the CH-acid ethyl cyanoacetate 2a to furnish the active olefin 9aa. This simple and environmentally friendly approach can be used to construct highly substituted hydrogenated products in a regioselective fashion with good yields.
Environmentally friendly one-pot synthesis of α-alkylated nitriles using hydrotalcite-supported metal species as multifunctional solid catalysts
Motokura, Ken,Fujita, Noriaki,Mori, Kohsuke,Mizugaki, Tomoo,Ebitani, Kohki,Jitsukawa, Koichiro,Kaneda, Kiyotomi
, p. 8228 - 8239 (2007/10/03)
A ruthenium-grafted hydrotalcite (Ru/HT) and hydrotalcite-supported palladium nanoparticles (Pdnano/ HT) are easily prepared by treating basic layered double hydroxide, hydrotalcite (HT, Mg6Al 2(OH)16CO3) with aqueous RuCl 3·n H2O and K2[PdCl4] solutions, respectively, using surface impregnation methods. Analysis by means of X-ray diffraction, and energydispersive X-ray, electron paramagnetic resonance, and X-ray absorption fine structure spectroscopies proves that a monomeric RuIV species is grafted onto the surface of the HT. Meanwhile, after reduction of a surface-isolated PdII species, highly dispersed Pd nanoclusters with a mean diameter of about 70 A is observed on the Pdnano/HT surface by transmission electron microscopy analysis. These hydrotalcite-supported metal catalysts can effectively promote α-alkylation reactions of various nitriles with primary alcohols or carbonyl compounds through tandem reactions consisting of metal-catalyzed oxidation and reduction, and an aldol reaction promoted by the base sites of the HT. In these catalytic α-alkylations, homogeneous bases are unnecessary and the only by-product is water. Additionally, these catalyst systems are applicable to one-pot syntheses of glutaronitrile derivatives.
A remarkable effect of bases on the catalytic radical addition of cyanoacetates to alkenes using a Mn(II)/Co(II)/O2 redox system
Kagayama, Takashi,Fuke, Takahiro,Sakaguchi, Satoshi,Ishii, Yasutaka
, p. 1673 - 1676 (2007/10/03)
A remarkable addition effect of bases, like AcOK, was observed in the radical addition of cyanoacetates to alkenes catalyzed by a Mn(II)/Co(II)/O 2 redox system. Thus, a carbon radical from ethyl cyanoacetate could be catalytically generated by
Tandem catalytic condensation and hydrogenation processes in ionic liquids
Baidossi, Mubeen,Joshi, Asutosh V.,Mukhopadhyay, Sudip,Sasson, Yoel
, p. 1885 - 1887 (2007/10/03)
A domino reaction composed of a Knoevenagel condensation combined with a simultaneous catalytic hydrogenation is reported in an ionic liquid solvent under mild conditions (298-363 K and 300 kPa). No interference between the catalysts (Pd/C and amine acetate salt) of the two diverse steps was monitored. The product could be neatly extracted by diethyl ether and the solvent containing the catalysts could be recycled and reused five times without any loss in activity or selectivity. The same methodology in a common organic solvent such as DMA resulted in significant competing parallel hydrogenation of the aldehyde to alcohol.
