58085-33-9Relevant academic research and scientific papers
Modular Cyclopentenone Synthesis through the Catalytic Molecular Shuffling of Unsaturated Acid Chlorides and Alkynes
Lee, Yong Ho,Denton, Elliott H.,Morandi, Bill
supporting information, p. 20948 - 20955 (2020/12/21)
We describe a general strategy for the intermolecular synthesis of polysubstituted cyclopentenones using palladium catalysis. Overall, this reaction is achieved via a molecular shuffling process involving an alkyne, an α,β-unsaturated acid chloride, which serves as both the alkene and carbon monoxide source, and a hydrosilane to create three new C-C bonds. This new carbon monoxide-free pathway delivers the products with excellent yields. Furthermore, the regioselectivity is complementary to conventional methods for cyclopentenone synthesis. In addition, a set of regio- and chemodivergent reactions are presented to emphasize the synthetic potential of this novel strategy.
Stereospecific Electrophilic Fluorocyclization of α,β-Unsaturated Amides with Selectfluor
Fei, Haiyang,Fu, Yao,Jalani, Hitesh B.,Li, Guigen,Lu, Hongjian,Wu, Hongmiao,Xu, Zheyuan,Zhu, Lin
supporting information, (2020/03/30)
An efficient fluorocyclization of α,β-unsaturated amides through a formal halocyclization process is developed. The reaction proceeds under transition-metal-free conditions and leads to the formation of fluorinated oxazolidine-2,4-diones with excellent regio- and diastereoselectivity. The evaluation of the reaction mechanism based on preliminary experiments and density functional theory calculations suggests that a synergetic syn-oxo-fluorination occurs and is followed by an anti-oxo substitution reaction. The reaction opens a new window in the field of stereospecific fluorofunctionalization.
Macrolactam Synthesis via Ring-Closing Alkene-Alkene Cross-Coupling Reactions
Goh, Jeffrey,Loh, Teck-Peng,Maraswami, Manikantha
supporting information, p. 9724 - 9728 (2020/12/21)
Reported herein is a practical method for macrolactam synthesis via a Rh(III)-catalyzed ring closing alkene-alkene cross-coupling reaction. The reaction proceeded via a Rh-catalyzed alkenyl sp2 C-H activation process, which allows access to macrocyclic molecules of different ring sizes. Macrolactams containing a conjugated diene framework could be easily prepared in high chemoselectivities and Z,E stereoselectivities.
N-Cinnamoylanthranilates as human TRPA1 modulators: Structure-activity relationships and channel binding sites
Chandrabalan, Arundhasa,McPhillie, Martin J.,Morice, Alyn H.,Boa, Andrew N.,Sadofsky, Laura R.
supporting information, p. 141 - 156 (2019/03/17)
The transient receptor potential ankyrin 1 (TRPA1) channel is a non-selective cation channel, which detects noxious stimuli leading to pain, itch and cough. However, the mechanism(s) of channel modulation by many of the known, non-reactive modulators has not been fully elucidated. N-Cinnamoylanthranilic acid derivatives (CADs) contain structural elements from the TRPA1 modulators cinnamaldehyde and flufenamic acid, so it was hypothesized that specific modulators could be found amongst them and more could be learnt about modulation of TRPA1 with these compounds. A series of CADs was therefore screened for agonism and antagonism in HEK293 cells stably transfected with WT-human (h)TRPA1, or C621A, F909A or F944A mutant hTRPA1. Derivatives with electron-withdrawing and/or electron-donating substituents were found to possess different activities. CADs with inductive electron-withdrawing groups were agonists with desensitising effects, and CADs with electron-donating groups were either partial agonists or antagonists. Site-directed mutagenesis revealed that the CADs do not undergo conjugate addition reaction with TRPA1, and that F944 is a key residue involved in the non-covalent modulation of TRPA1 by CADs, as well as many other structurally distinct non-reactive TRPA1 ligands already reported.
Nickel-Catalyzed Decarbonylative Cyanation of Acyl Chlorides
Wang, Zhenhua,Wang, Xiu,Ura, Yasuyuki,Nishihara, Yasushi
supporting information, p. 6779 - 6784 (2019/08/26)
Ni-catalyzed decarbonylative cyanation of acyl chlorides with trimethylsilyl cyanide has been achieved. This transformation is applicable to the synthesis of an array of nitrile compounds bearing a wide range of functional groups under neutral conditions. The step-by-step experimental studies revealed that the reaction sequences of the present catalytic reaction are oxidative addition, transmetalation, decarbonylation, and reductive elimination.
Macrolide Synthesis through Intramolecular Oxidative Cross-Coupling of Alkenes
Jiang, Bing,Zhao, Meng,Li, Shu-Sen,Xu, Yun-He,Loh, Teck-Peng
supporting information, p. 555 - 559 (2018/02/21)
A RhIII-catalyzed intramolecular oxidative cross-coupling between double bonds for the synthesis of macrolides is described. Under the optimized reaction conditions, macrocycles containing a diene moiety can be formed in reasonable yields and with excellent chemo- and stereoselectivity. This method provides an efficient approach to synthesize macrocyclic compounds containing a 1,3-conjugated diene structure.
Novel and practical asymmetric synthesis of β2,3-amino esters using asymmetric Michael addition of chiral amine
Ozeki, Minoru,Egawa, Honoka,Takano, Toshiki,Mizutani, Hideki,Yasuda, Narumi,Arimitsu, Kenji,Kajimoto, Tetsuya,Hosoi, Shinzo,Iwasaki, Hiroki,Kojima, Naoto,Node, Manabu,Yamashita, Masayuki
supporting information, p. 2014 - 2021 (2017/03/20)
A practical method for the synthesis of chiral β2,3-amino esters having various substituents was developed, which is characterized by an asymmetric Michael addition reaction of a chiral lithium amide with trisubstituted (E)-α,β-unsaturated esters. We found that a highly face-selective protonation occurred by the quick addition of water to the enolate intermediate derived from the Michael addition reaction to afford N-protected β2,3-amino esters in moderate to excellent yields. This finding was made possible by the facile preparation of geometrically pure trisubstituted (E)-α,β-unsaturated esters, which was established recently by our group. The subsequent deprotection of the amino group in the Michael adduct by using N-iodosuccinimide (NIS) efficiently provided β2,3-amino esters having various substituents.
Pd-catalyzed dehydrogenative aryl-aryl bond formation via double C(sp2)-H bond activation: Efficient synthesis of [3,4]-fused oxindoles
Bunescu, Ala,Piou, Tiffany,Wang, Qian,Zhu, Jieping
supporting information, p. 334 - 337 (2015/03/03)
A Pd(0)-catalyzed double cyclization of easily available o-bromoanilides leading to strained [3,4]-fused oxindoles was developed. The reaction proceeded through a highly ordered sequence involving key carbopalladation, 1,4-Pd migration, and C(sp2)-H functionalization steps. (Chemical Equation Presented).
Synthesis of 2-(hetero)aryl-5-(trimethylsilylethynyl)oxazoles from (hetero)arylacrylic acids
Pankova, Alena S.,Stukalov, Alexander Yu.,Kuznetsov, Mikhail A.
supporting information, p. 1826 - 1829 (2015/04/27)
A three-step method for the synthesis of 2-(hetero)aryl-5-(trimethylsilylethynyl)oxazoles is described. Easily accessible bis(trimethylsilyl)acetylene and acrylic acid derivatives are used as starting materials for the preparation of mono- and disubstituted 5-(trimethylsilyl)pent-1-en-4-yn-3-ones. Oxidative phthalimidoaziridination of these enynones provides the key 2-acyl-1-phthalimidoaziridines that are further utilized in the thermal expansion of the three-membered ring to furnish the target functionalizable oxazoles.
Enantioselective palladium(0)-catalyzed nazarov-type cyclization
Kitamura, Kei,Shimada, Naoyuki,Stewart, Craig,Atesin, Abdurrahman C.,Atein, Tülay A.,Tius, Marcus A.
supporting information, p. 6288 - 6291 (2015/05/20)
A Pd0-catalyzed asymmetric Nazarov-type cyclization is described. The optimized ligand for the reaction incorporates a weakly coordinating pyridine ring into a TADDOL-derived phosphoramidite (TADDOL=α,α,α,α-tetraaryl-1,3-dioxolane-4,5-dimethanol). The reaction leads to the formation of cyclopentenones as single diastereoisomers that incorporate two contiguous asymmetric centers, one tertiary and one an all-carbon-atom quaternary stereocenter, in high yield and optical purity. It is noteworthy that the reaction does not require that substrates should be activated by aryl substituents.
