77620-05-4Relevant academic research and scientific papers
Indium-Catalyzed C?F Bond Transformation through Oxymetalation/β-Fluorine Elimination to Access Fluorinated Isocoumarins
Yata, Tetsuji,Nishimoto, Yoshihiro,Chiba, Kouji,Yasuda, Makoto
, p. 8288 - 8294 (2021/05/21)
Fluorinated heterocycles have attracted much attention in the pharmaceutical and agrochemical industries. Many strategies have already been developed to achieve the synthesis of fluorinated heterocycles. Formidable challenges remain, however, in the synthesis of fluorinated isocoumarin derivatives that are among the most alluring structural motifs. Herein, the indium-catalyzed C?F bond transformation of 2-(2,2-difluorovinyl) benzoates is reported, which are readily accessible compounds, to give a diverse array of fluorinated isocoumarins. The present reaction proceeds smoothly using inexpensive reagents: a catalytic amount of indium salt in the presence of zinc salt. A theoretical calculation of potential energy profiles showed that the reaction consists of oxymetalation with the elimination of alkyl halide and the β-fluorine elimination.
Sterically Shielded, Stabilized Nitrile Imine for Rapid Bioorthogonal Protein Labeling in Live Cells
An, Peng,Lewandowski, Tracey M.,Erbay, Tug?e G.,Liu, Peng,Lin, Qing
, p. 4860 - 4868 (2018/04/16)
In pursuit of fast bioorthogonal reactions, reactive moieties have been increasingly employed for selective labeling of biomolecules in living systems, posing a challenge in attaining reactivity without sacrificing selectivity. To address this challenge, here we report a bioinspired strategy in which molecular shape controls the selectivity of a transient, highly reactive nitrile imine dipole. By tuning the shape of structural pendants attached to the ortho position of the N-aryl ring of diaryltetrazoles-precursors of nitrile imines, we discovered a sterically shielded nitrile imine that favors the 1,3-dipolar cycloaddition over the competing nucleophilic addition. The photogenerated nitrile imine exhibits an extraordinarily long half-life of 102 s in aqueous medium, owing to its unique molecular shape that hinders the approach of a nucleophile as shown by DFT calculations. The utility of this sterically shielded nitrile imine in rapid (~1 min) bioorthogonal labeling of glucagon receptor in live mammalian cells was demonstrated.
Highly enantioselective synthesis of 2,3-dihydro-1 H-imidazo[2,1-a isoindol-5(9b H)-ones via catalytic asymmetric intramolecular cascade imidization-nucleophilic addition-lactamization
He, Yuwei,Cheng, Chuyu,Chen, Bin,Duan, Kun,Zhuang, Yue,Yuan, Bo,Zhang, Meisan,Zhou, Yougui,Zhou, Zihong,Su, Yu-Jun,Cao, Rihui,Qiu, Liqin
supporting information, p. 6366 - 6369 (2015/01/16)
Highly enantioselective catalytic asymmetric intramolecular cascade imidization-nucleophilic addition-lactamization of N1-alkylethane-1,2-diamine with methyl 2-formylbenzoate catalyzed by a chiral phosphoric acid represents the first efficient method for the preparation of medicinally interesting chiral 2,3-dihydro-1H-imidazo[2,1-a]isoindol-5(9bH)-ones with high yields and excellent enantioselectivities. This strategy has been shown to be quite general toward various methyl 2-formylbenzoates.
A synthetic route to chiral C(3)-functionalized phthalides via a Ag(I)-catalyzed allylation/transesterification sequence
Mirabdolbaghi, Roya,Dudding, Travis
, p. 3287 - 3292 (2013/04/24)
A Ag(I)-catalyzed synthesis of chiral C(3)-substituted phthalides (8a-f) via a Sakurai-Hosomi allylation/transesterification reaction is described (ee ≤86%). A notable feature of this reaction is that it utilizes ortho-substituted aldehydes, which are a class of compounds that generally afford poor levels of stereoinduction when applying most known catalytic asymmetric allylation approaches. It was also found that elongation of the n-alkyl chain length (R1, up to n=6; R2=H) of the starting alkyl 2-formylbenzoates (7g-i) improved the enantiomeric excess (ee) of the product.
An indium-mediated allylative/transesterification DFT-directed approach to chiral C(3)-functionalized phthalides
Mirabdolbaghi, Roya,Dudding, Travis
, p. 3748 - 3751 (2012/09/07)
A one-pot synthesis of chiral C(3)-substituted phthalides via an indium-mediated allylation/transesterification reaction is described. The development of this reaction was facilitated through the applied use of DFT calculations to rationalize the stereoselection of a chiral In-mediated process. It was discovered that the enantiomeric excess of this reaction depended upon the steric size, chain length, and substitution of the aldehyde employed.
Synthesis and characterization of π-extended porphyrins as potential precursors for the formation of columnar mesophases: Design principles for columnar mesophases need revision?
Herzog, Beat,Neier, Reinhard
scheme or table, p. 29 - 44 (2011/06/18)
A series of meso-a bridged extended porphyrins substituted with long aliphatic chains were synthesized and fully characterized. Two different synthetic strategies were tested to obtain the target structures. The synthetic steps were optimized in order to obtain scalable routes for the production of sufficient quantities of η-extended porphyrins for material science studies. The porphyrins were obtained either as free bases or complexed with Ni II or CuII. UV-Vis spectroscopy and polarized light microscopy was used for the analysis of the material properties of the η-extended porphyrins. The results obtained with our compounds are not compatible with the results reported in the literature. ARKAT-USA, Inc.
Synthesis of chiral 3-substituted phthalides by a sequential organocatalytic enantioselective aldol-lactonization reaction. Three-step synthesis of (S)-(-)-3-butylphthalide
Zhang, Haoyi,Zhang, Shilei,Liu, Lu,Luo, Guangshun,Duan, Wenhu,Wang, Wei
supporting information; experimental part, p. 368 - 374 (2010/03/30)
(Chemical Equation Presented) The development of efficient methods for the facile construction of important molecular frameworks is an important goal in organic synthesis. Chiral 3-substituted phthalides are widely distributed in a large collection of natural products with broad, potent, and potentially path-pointing biological activities. In this investigation, we have uncovered an unprecedented organocatalytic asymmetric aldol-lactonization reaction of 2-formylbenzoic esters with ketones/aldehydes for convenient construction of the enantioenriched "privileged" scaffold. As a result of the sensitive nature of substrate structures of an organocatalytic enantioselective aldol reaction, after extensive optimization of reaction conditions, catalyst L-prolinamide alcohol IV is identified as the best promoter. Interestingly, it is found that in this reaction, addition of an acid additive PhCO2H can significantly enhance reaction efficiency with use of only as low as 2.5 mol % IV for the process. Moreover, due to the sensitivity of reaction conditions toward a sequential aldol-lactonization process without affecting enantioselectivity and racemization, it is essential to remove the catalyst for the subsequent facile lactonization reaction in the presence of K 2CO3. The aldol-lactonization processes serve as a powerful approach to the preparation of synthetically and biologically important 3-substitued phthalides with a high level of enantioselectivities. A 3-step catalytic asymmetric synthesis of the natural product of 3-butylphthalide is reported.
Synthesis of isocoumarins via palladium catalyzed reactions of methyl 2- (2',2'-dibromovinyl)benzoates
Wang, Le,Shen, Wang
, p. 7625 - 7628 (2007/10/03)
3-Substituted isocoumarins are synthesized in good to excellent yields via palladium catalyzed coupling of 2-(2',2'-dibromovinyl)benzoates and organostannanes. The process involves a Stille reaction, and a subsequent annulation reaction.
