376641-58-6Relevant academic research and scientific papers
Access to Trisubstituted Fluoroalkenes by Ruthenium-Catalyzed Cross-Metathesis
Nouaille, Augustin,Pannecoucke, Xavier,Poisson, Thomas,Couve-Bonnaire, Samuel
, p. 2140 - 2147 (2021/03/06)
Although the olefin metathesis reaction is a well-known and powerful strategy to get alkenes, this reaction remained highly challenging with fluororalkenes, especially the Cross-Metathesis (CM) process. Our thought was to find an easy accessible, convenient, reactive and post-functionalizable source of fluoroalkene, that we found as the methyl 2-fluoroacrylate. We reported herein the efficient ruthenium-catalyzed CM reaction of various terminal and internal alkenes with methyl 2-fluoroacrylate giving access, for the first time, to trisubstituted fluoroalkenes stereoselectively. Unprecedent TON for CM involving fluoroalkene, up to 175, have been obtained and the reaction proved to be tolerant and effective with a large range of olefin partners giving fair to high yields in metathesis products. (Figure presented.).
Synthesis and inhibitory studies of phosphonic acid analogues of homophenylalanine and phenylalanine towards alanyl aminopeptidases
Wanat, Weronika,Talma, Micha?,Dziuk, B?a?ej,Kafarski, Pawe?
, p. 1 - 22 (2020/09/18)
A library of novel phosphonic acid analogues of homophenylalanine and phenylalanine, containing fluorine and bromine atoms in the phenyl ring, have been synthesized. Their inhibitory properties against two important alanine aminopeptidases, of human (hAPN, CD13) and porcine (pAPN) origin, were evaluated. Enzymatic studies and comparison with literature data indicated the higher inhibitory potential of the homophenylalanine over phenylalanine derivatives towards both enzymes. Their inhibition constants were in the submicromolar range for hAPN and the micromolar range for pAPN, with 1-amino-3-(3-fluorophenyl) propylphosphonic acid (compound 15c) being one of the best low-molecular inhibitors of both enzymes. To the best of our knowledge, P1 homophenylalanine analogues are the most active inhibitors of the APN among phosphonic and phosphinic derivatives described in the literature. Therefore, they constitute interesting building blocks for the further design of chemically more complex inhibitors. Based on molecular modeling simulations and SAR (structure-activity relationship) analysis, the optimal architecture of enzyme-inhibitor complexes for hAPN and pAPN were determined.
Nickel-Catalyzed Alkyl-Alkyl Cross-Electrophile Coupling Reaction of 1,3-Dimesylates for the Synthesis of Alkylcyclopropanes
Chen, Pan-Pan,Hong, Xin,Jarvo, Elizabeth R.,McGinnis, Tristan M.,Sanford, Amberly B.,Thane, Taylor A.
supporting information, (2020/03/23)
Cross-electrophile coupling reactions of two Csp3-X bonds remain challenging. Herein we report an intramolecular nickel-catalyzed cross-electrophile coupling reaction of 1,3-diol derivatives. Notably, this transformation is utilized to synthesize a range of mono- and 1,2-disubstituted alkylcyclopropanes, including those derived from terpenes, steroids, and aldol products. Additionally, enantioenriched cyclopropanes are synthesized from the products of proline-catalyzed and Evans aldol reactions. A procedure for direct transformation of 1,3-diols to cyclopropanes is also described. Calculations and experimental data are consistent with a nickel-catalyzed mechanism that begins with stereoablative oxidative addition at the secondary center.
Enantioselective Synthesis of 4-Methyl-3,4-dihydroisocoumarin via Asymmetric Hydroformylation of Styrene Derivatives
Qu, Bo,Tan, Renchang,Herling, Madison R.,Haddad, Nizar,Grinberg, Nelu,Kozlowski, Marisa C.,Zhang, Xumu,Senanayake, Chris H.
, p. 4915 - 4920 (2019/03/19)
Enantioenriched aldehydes are produced through asymmetric hydroformylation of styrene derivatives using BIBOP-type ligands. The featured example is enantioselective synthesis of 4-methyl-3,4-dihydroisocoumarin, which was prepared in a 95.1:4.9 enantiomeric ratio from asymmetric hydroformylation of ethyl 2-vinylbenzoate followed by in situ lactonization during the reduction process. The conditions are compatible with both electron-rich and electron-poor substituents.
Beyond classical reactivity patterns: Hydroformylation of vinyl and allyl arenes to valuable β- And γ-aldehyde intermediates using supramolecular catalysis
Dydio, Pawe?,Detz, Remko J.,De Bruin, Bas,Reek, Joost N. H.
supporting information, p. 8418 - 8429 (2014/06/24)
In this study, we report on properties of a series of rhodium complexes of bisphosphine and bisphosphite L1-L7 ligands, which are equipped with an integral anion binding site (the DIM pocket), and their application in the regioselective hydroformylation of vinyl and allyl arenes bearing an anionic group. In principle, the binding site of the ligand is used to preorganize a substrate molecule through noncovalent interactions with its anionic group to promote otherwise unfavorable reaction pathways. We demonstrate that this strategy allows for unprecedented reversal of selectivity to form otherwise disfavored β-aldehyde products in the hydroformylation of vinyl 2- and 3-carboxyarenes, with chemo- and regioselectivity up to 100%. The catalyst has a wide substrate scope, including the most challenging substrates with internal double bonds. Coordination studies of the catalysts under catalytically relevant conditions reveal the formation of the hydridobiscarbonyl rhodium complexes [Rh(Ln)(CO)2H]. The titration studies confirm that the rhodium complexes can bind anionic species in the DIM binding site of the ligand. Furthermore, kinetic studies and in situ spectroscopic investigations for the most active catalyst give insight into the operational mode of the system, and reveal that the catalytically active species are involved in complex equilibria with unusual dormant (reversibly inactivated) species. In principle, this involves the competitive inhibition of the recognition center by product binding, as well as the inhibition of the metal center via reversible coordination of either a substrate or a product molecule. Despite the inhibition effects, the substrate preorganization gives rise to very high activities and efficiencies (TON > 18‰000 and TOF > 6000 mol mol-1 h-1), which are adequate for commercial applications.
Supramolecular control of selectivity in hydroformylation of vinyl arenes: Easy access to valuable β-aldehyde intermediates
Dydio, Pawel,Reek, Joost N. H.
supporting information, p. 3878 - 3882 (2013/05/09)
Go against the flow! A rationally designed regioselective hydroformylation catalyst, [Rh/L], in which noncovalent ligand-substrate interactions allow the unprecedented reversal of selectivity from the typical α-aldehyde to the otherwise unfavored product β-aldehyde, is reported. This catalytic system opens up novel and sustainable synthetic pathways to important intermediates for the fine-chemicals industry.
Tyrosine phosphatase inhibitors
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, (2008/06/13)
A compound of the formula (I): wherein X1 and X2 are the same or different and each is a bond or a spacer having 1 to 20 atom(s) in the main chain; one of R1 and R2 is a cycle group having substituent(s) selected from 1) an optionally substituted carboxy-C1-6 alkoxy group and 2) an optionally substituted carboxy-C1-6 aliphatic hydrocarbon group, wherein the cycle group optionally has additional substituent(s), and the other is an optionally substituted cycle group or a hydrogen atom; and R3, R4 and R5 are the same or different and each is a hydrogen atom or a substituent, or R4 may link together with R3 or R5 to form an optionally substituted ring; provided that when R3 is a hydrogen atom, R4 is a hydrogen atom and R5 is methyl, X2—R2 is not 4-cyclohexylphenyl; when R3 is 4-methoxyphenyl, R4 is a hydrogen atom and R5 is methyl, X2—R2 is not 4-methoxyphenyl; and when R1 or R2 is a hydrogen atom, the adjacent X1 or X2 is not a C1-7 alkylene; or a salt thereof exhibits a protein tyrosine phosphatase inhibitory action and is useful as a prophylactic or therapeutic agent for diabetes or the like.
