610-89-9Relevant academic research and scientific papers
Synthesis and 1,3-dipolar cycloaddition reactions of new pyrazolo[1,5,4-ef][1,5]benzodiazepines
Bouissane, Latifa,El Kazzouli, Said,Rakib, El Mostapha,Khouili, Mostafa,Hannioui, Abdellah,Benchidmi, Mohammed,Essassi, El Mokhtar,Guillaumet, Ge?rald
, p. 1651 - 1658 (2004)
New pyrazolo[1,5,4-ef][1,5]benzodiazepines have been synthesized by condensation of 7-aminoindazole with β-keto esters, alkylation and 1,3-dipolar cycloaddition. The peri- and regioselective cycloaddition of allylpyrazolo-1,5-benzodiazepinones and 2,4,6-t
Asymmetric Allylation of 2-Oxocycloalkanecarboxylates
Yoshida, Masanori,Yano, Shohei,Hara, Shoji
, p. 1295 - 1300 (2017)
In this study, the highly enantioselective α-allylation of α-substituted β-ketoesters, particularly 2-oxocycloalkanecarboxylates, is achieved by synergistic catalysis with an achiral palladium complex and a chiral primary amino acid. Various α-allylated β-ketoesters containing a quaternary carbon stereogenic center are synthesized in high yields (up to 97%) with excellent enantioselectivity (up to 99% ee).
Synthesis and biochemical evaluation of warhead-decorated psoralens as (Immuno)proteasome inhibitors
?terman, Andrej,Gobec, Martina,Gobec, Stanislav,Mravljak, Janez,Proj, Matic,Rejc, Luka,Schiffrer, Eva Shannon,Sosi?, Izidor
, (2021/06/28)
The immunoproteasome is a multicatalytic protease that is predominantly expressed in cells of hematopoietic origin. Its elevated expression has been associated with autoimmune diseases, various types of cancer, and inflammatory diseases. Selective inhibit
Accumulation of Active Species in Silica Mesopore: Effect of the Pore Size and Free Base Additives on Pd-catalyzed Allylation using Allylic Alcohol
Chun, Wang-Jae,Kawashima, Sae,Manaka, Yuichi,Motokura, Ken,Nambo, Masayuki
, (2020/04/17)
A mesoporous silica-supported Pd complex was prepared using various types of porous silica supports (pore size: 16–31 ?). The effects of the pore size and base additive properties on the catalytic allylation were investigated. The activity of the Pd-catal
Electrochemical oxidative cyclization of olefinic carbonyls with diselenides
Guan, Zhipeng,Wang, Yunkun,Wang, Huamin,Huang, Yange,Wang, Siyuan,Tang, Hongding,Zhang, Heng,Lei, Aiwen
supporting information, p. 4976 - 4980 (2019/09/30)
The tandem cyclization of olefinic carbonyls with easily accessible diselenides facilitated by electrochemical oxidation has been successfully developed, which provides an environmentally friendly method for the construction of C-Se and C-O bonds simultaneously. A series of seleno dihydrofurans and seleno oxazolines, bearing fragile heterocycles, subtle C-I bonds and supernumerary vinyl groups, were forged using this elegant chelation strategy. Neither metal catalysts nor external chemical oxidants are required to promote this transformation.
Silica Support-Enhanced Pd-Catalyzed Allylation Using Allylic Alcohols
Motokura, Ken,Ikeda, Marika,Kim, Minjune,Nakajima, Kiyotaka,Kawashima, Sae,Nambo, Masayuki,Chun, Wang-Jae,Tanaka, Shinji
, p. 4536 - 4544 (2018/09/21)
Although allylation using allylic alcohol is an environmentally-friendly method because of water being the sole byproduct in such reactions, allylic alcohol is one of the most difficult allylating agents in Pd-catalyzed allylation of nucleophiles. In this study, we successfully developed a mesoporous silica-supported Pd complex as an efficient catalyst for the allylation of nucleophiles using allylic alcohols as allylating agents. The allylic alcohol is activated by the silanol group on the support surface, which easily undergoes a π-allylpalladium intermediate formation. The catalytic activity of the supported Pd complex was ca. 9 times higher than that of its homogeneous precursor Pd complex. A highest turnover number of 4500 based on Pd was achieved. Various nucleophiles and allylic alcohol derivatives could be used as substrates. Not only the detailed catalyst structure but also the reaction mechanism including the concerted activation of allylic alcohol by the Pd complex and silanol were investigated by several spectroscopic techniques, such as Pd K-edge XAFS, solid-state NMR, and in-situ FT-IR measurements.
A distinctive transformation based diversity oriented synthesis of small ring carbocycles and heterocycles from biocatalytically derived enantiopure α-substituted-β-hydroxyesters
Halder, Joydev,Das, Debabrata,Nanda, Samik
, p. 2549 - 2575 (2018/04/12)
A series of structurally novel small ring carbocyclic and heterocyclic molecules were accessed in an enantiopure fashion. The starting materials, α-substituted-β-hydroxyesters, were achieved through the biocatalytic dynamic kinetic resolution of parent β-
Ni-Catalyzed Regioselective Dicarbofunctionalization of Unactivated Olefins by Tandem Cyclization/Cross-Coupling and Application to the Concise Synthesis of Lignan Natural Products
Kc, Shekhar,Basnet, Prakash,Thapa, Surendra,Shrestha, Bijay,Giri, Ramesh
, p. 2920 - 2936 (2018/03/09)
We disclose a (terpy)NiBr2-catalyzed reaction protocol that regioselectively difunctionalizes unactivated olefins with tethered alkyl halides and arylzinc reagents. The reaction shows an excellent functional group tolerance (such as ketones, es
Tunable Aerobic Oxidative Hydroxylation/Dehydrogenative Homocoupling of Pyrazol-5-ones under Transition-Metal-Free Conditions
Sheng, Xuguang,Zhang, Jinlong,Yang, Huameng,Jiang, Gaoxi
supporting information, p. 2618 - 2621 (2017/05/24)
A practical and tunable transition-metal-free aerobic oxidation of pyrazol-5-ones preparing either 4-hydroxypyrazoles (via C-H hydroxylation) or bispyrazoles (via dehydrogenative homocoupling) is described. The K2CO3/dioxane reagent system predominately promoted hydroxylation to deliver the α-hydroxylated pyrazoles. In contrast, the formation of bispyrazoles was overwhelmingly preferred with CH3CN as the reaction medium without any additives.
Concerted Catalysis in Tight Spaces: Palladium-Catalyzed Allylation Reactions Accelerated by Accumulated Active Sites in Mesoporous Silica
Motokura, Ken,Ikeda, Marika,Nambo, Masayuki,Chun, Wang-Jae,Nakajima, Kiyotaka,Tanaka, Shinji
, p. 2924 - 2929 (2017/08/15)
The surface of mesoporous silica was modified with a Pd–bisphosphine complex and/or a tertiary amine group for concerted acceleration of allylation reactions. Mesoporous-silica-supported catalysts with a 1.6 nm pore diameter showed higher performance than nonporous or larger mesoporous silica-supported catalysts owing to the accumulation of active sites into a confined space. For the case in which allyl alcohol was used in the reaction, the presence of a silanol group on the surface was quite effective: the turnover number of Pd was nine times greater than that of the homogeneous Pd complex.
