- Construction of isoxazolone-fused phenanthridinesviaRh-catalyzed cascade C-H activation/cyclization of 3-arylisoxazolones with cyclic 2-diazo-1,3-diketones
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A Rh(iii)-catalyzed cascade C-H activation/intramolecular cyclization of 3-aryl-5-isoxazolones with cyclic 2-diazo-1,3-diketones was described, leading to the formation of isoxazolo[2,3-f]phenanthridine skeletons. The protocol features the simultaneous one-pot formation of two new C-C/C-N bonds and one heterocycle in moderate-to-good yields with good functional group compatibility. It is amenable to large-scale synthesis and further transformation.
- Hu, Wangcheng,He, Xinwei,Zhou, Tongtong,Zuo, Youpeng,Zhang, Shiwen,Yang, Tingting,Shang, Yongjia
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supporting information
p. 552 - 556
(2021/02/06)
-
- Iridium-Catalyzed Enantioselective and Diastereoselective Hydrogenation of Racemic β’-Keto-β-Amino Esters via Dynamic Kinetic Resolution
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An iridium/f-diaphos catalytic system for the enantioselective hydrogenation of α-substituted β-ketoesters via dynamic kinetic resolution is reported. The desired anti β’-hydroxy-β-amino esters were obtained in moderate to good yields (60–95%) with 72–99% ees and 91:9 to 99:1 drs. This protocol tolerates various functional groups and could be easily conducted on gram scale with lower catalyst loading (TON up to 9100). (Figure presented.).
- He, Jiayin,Huang, An,Ling, Fei,Wang, Shiliang,Wang, Yifan,Wang, Ze,Zhao, Xianghua,Zhong, Weihui
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supporting information
p. 4714 - 4719
(2021/09/02)
-
- Amide/Ester Cross-Coupling via C-N/C-H Bond Cleavage: Synthesis of β-Ketoesters
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Activated primary, secondary, and tertiary amides were coupled with enolizable esters in the presence of LiHMDS to obtain good yields of β-ketoesters at room temperature. Notably, this protocol provides an efficient, mild, and high chemoselectivity method
- Chen, Jiajia,Joseph, Devaneyan,Xia, Yuanzhi,Lee, Sunwoo
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p. 5943 - 5953
(2021/04/02)
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- Radical Aza-Cyclization of α-Imino-oxy Acids for Synthesis of Alkene-Containing N-Heterocycles via Dual Cobaloxime and Photoredox Catalysis
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Nitrogen-containing heterocycles are prevalent in both naturally and synthetically bioactive molecules. We report herein an unprecedented protocol for radical aza-cyclization of α-imino-oxy acids with pendant alkenes via synergistic photoredox and cobaloxime catalysis. With or without alkenes as the intermolecular cross-coupling partners, the transformation provides a variety of corresponding alkene-containing dihydropyrrole products in satisfactory yields. In the presence of external alkenes, the tandem reaction generates E-selective coupling products with excellent chemo- and stereoselectivity.
- Tu, Jia-Lin,Liu, Jia-Li,Tang, Wan,Su, Ma,Liu, Feng
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supporting information
p. 1222 - 1226
(2020/02/15)
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- An efficient route for the synthesis of N-(1H-benzo[d]imidazol-2-yl)benzamide derivatives promoted by CBr4 in one pot
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A metal-free one-pot method for the synthesis of N-(1H-benzo[d]imidazol-2-yl)benzamide derivatives was proposed mediated by CBr4. The reaction went through ring formation and opening processes with only two protons leaving and the thermodynamically favorable products were selectively formed in moderate to good yields.
- Li, Songhua,Li, Yunyi,Ma, Chen,Xie, Caixia
-
-
- Desymmetrization of meso-dicarbonatecyclohexene with β-Hydrazino carboxylic esters via a Pd-catalyzed allylic substitution cascade
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The desymmetrization of meso-dicarbonatecyclohexene with β-hydrazino carboxylic esters has been achieved via a RuPHOX/Pd-catalyzed allylic substitution cascade for the construction of chiral hexahydrocinnoline derivatives with high performance. Mechanistic studies reveal that the reaction exploits a pathway different from that of our previous work and that the first nitrogen nucleophilic process is the rate-determining step. The protocol could be conducted on a gram scale without any loss of catalytic behavior, and the corresponding chiral hexahydrocinnolines can undergo diverse transformations.
- Xu, Kai,Zheng, Yan,Ye, Yong,Liu, Delong,Zhang, Wanbin
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supporting information
p. 8836 - 8841
(2020/11/30)
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- Improved synthesis of sterically encumbered heteroaromatic biaryls from aromatic β-keto esters
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A protocol for the synthesis of hindered 4-aryl 2-aminopyrimidines from β–keto esters is described. The process employs trifluoroethanol as an essential additive to promote the guanidine condensation reaction, enabling the synthesis of 25 aryl- and heteroaryl substituted aminopyrimidines in good yields and high purities with no column chromatography. The conditions described herein are readily scalable and have been employed in the large-scale synthesis of the clinical A2a/A2bR antagonist AB928.
- Rosen, Brandon R.,Ul Sharif, Ehesan,Miles, Dillon H.,Chan, Nicholas S.,Leleti, Manmohan R.,Powers, Jay P.
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- Synthesis of Dithiolethiones and Identification of Potential Neuroprotective Agents via Activation of Nrf2-Driven Antioxidant Enzymes
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Oxidative stress is implicated in the pathogenesis of a wide variety of neurodegenerative disorders, and accordingly, dietary supplement of exogenous antioxidants or/and upregulation of the endogenous antioxidant defense system are promising for therapeutic intervention or chemoprevention of neurodegenerative diseases. Nrf2, a master regulator of the cellular antioxidant machinery, cardinally participates in the transcription of cytoprotective genes against oxidative/electrophilic stresses. Herein, we report the synthesis of 59 structurally diverse dithiolethiones and evaluation of their neuroprotection against 6-hydroxydopamine-or H2O2-induced oxidative damages in PC12 cells, a neuron-like rat pheochromocytoma cell line. Initial screening identified compounds 10 and 11 having low cytotoxicity but conferring remarkable protection on PC12 cells from oxidative-mediated damages. Further studies demonstrated that both compounds upregulated a battery of antioxidant genes as well as corresponding genes' products. Significantly, silence of Nrf2 expression abolishes cytoprotection of 10 and 11, indicating targeting Nrf2 activation is pivotal for their cellular functions. Taken together, the two lead compounds discovered here with potent neuroprotective functions against oxidative stress via Nrf2 activation merit further development as therapeutic or chemopreventive candidates for neurodegenerative disorders.
- Bai, Feifei,Fang, Jianguo,Song, Zi-Long,Zhang, Baoxin
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p. 2214 - 2231
(2020/03/06)
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- Two Competitive but Switchable Organocatalytic Cascade Reaction Pathways: The Diversified Synthesis of Chiral Acetal-Containing Bridged Cyclic Compounds
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The organocatalytic enantioselective synthesis of methanobenzodioxepine derivatives bearing a 6,6,5-bridged ring system is presented. The m-CPBA-triggered in situ α-oxidation of β-oxoesters to provide the required but unstable α-hydroxy-β-dicarbonyl substrates is the key to this three-step sequence, providing the desired cyclic acetals with excellent stereoselectivities containing two bridgehead and one fully substituted stereocenters. It is noteworthy that the absence of m-CPBA furnished the acetal products bearing a 6,6,6-bridged ring system with similar good results from the same starting materials.
- Lv, Xue-Jiao,Chen, Ying-Han,Liu, Yan-Kai
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supporting information
p. 190 - 195
(2019/01/11)
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- Rate Enhancement in CAN-Promoted Pd(PPh3)2Cl2-Catalyzed Oxidative Cyclization: Synthesis of 2-Ketofuran-4-carboxylate Esters
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Stoichiometric ceric ammonium nitrate (CAN) and a catalytic amount of Pd(PPh3)2Cl2 (5 mol %) can rapidly produce multisubstituted 2-ketofuran-4-carboxylate esters from 2-propargylic 1,3-ketoesters via oxidative O-cyclization reaction. Pd(PPh3)2Cl2 was found to be the crucial catalyst as its inclusion greatly enhanced the rate of the reaction and cleanly afforded the products within minutes. Over 30 substrates were successfully converted to the desired compounds in mostly moderate to good yields.
- Ruengsangtongkul, Sureeporn,Chaisan, Nattawadee,Thongsornkleeb, Charnsak,Tummatorn, Jumreang,Ruchirawat, Somsak
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supporting information
p. 2514 - 2517
(2019/04/30)
-
- PhIO/Et3N ? 3HF-Mediated Formation of Fluorinated 2H-Azirines via Domino Fluorination/Azirination Reaction of Enamines
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A variety of enamine carboxylic esters and enaminones were converted to the biologically interesting fluorinated 2H-azirines through reactions with PhIF2 generated in situ by PhIO and Et3N ? 3HF in 1,2-dichroloethane, which features the hypervalent iodine reagents-mediated introduction of fluorine atom and formation of the 2H-azirine skeleton under metal-free conditions. The domino reaction is postulated to proceed via a PhIF2-mediated oxidative fluorination and a subsequent azirination of the fluorinated enamine intermediates. (Figure presented.).
- Zhang, Yong,Zhao, Xiaoyuan,Zhuang, Chen,Wang, Senlin,Zhang-Negrerie, Daisy,Du, Yunfei
-
supporting information
p. 2107 - 2112
(2018/04/19)
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- In situ generation of nitrile oxides from copper carbene and tert -butyl nitrite: Synthesis of fully substituted isoxazoles
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Herein, we present a novel [3 + 2] cycloaddition reaction of β-keto esters with nitrile oxides, which were generated in situ from copper carbene and tert-butyl nitrite. This three-component reaction provides new methodology for the direct synthesis of fully substituted isoxazole derivatives, featuring mild reaction conditions, readily accessible starting materials and simple operation. The experimental studies and DFT calculations suggest that the reaction starts with the generation of the key intermediate nitrile oxides, followed by a [3 + 2] cycloaddition reaction of β-keto esters to give the final isoxazole products.
- Chen, Rongxiang,Ogunlana, Abosede Adejoke,Fang, Shangwen,Long, Wenhao,Sun, Hongmei,Bao, Xiaoguang,Wan, Xiaobing
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supporting information
p. 4683 - 4687
(2018/07/06)
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- Bromide-Mediated C-H Bond Functionalization: Intermolecular Annulation of Phenylethanone Derivatives with Alkynes for the Synthesis of 1-Naphthols
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Bromide-mediated intermolecular annulation of phenylethanone derivatives with alkynes has been developed, which allows for the regioselective formation of polysubstituted 1-naphthols. The usage of readily available bromine catalyst, broad substrate scope, and mild conditions make this protocol very practical. Mechanistic investigations reveal that the bromination of phenylethanone derivatives occurs to yield bromo-substituted intermediates, which react in situ with alkynes to furnish the desired 1-naphthols.
- Lu, Tao,Jiang, Ya-Ting,Ma, Feng-Ping,Tang, Zi-Jing,Kuang, Liu,Wang, Yu-Xuan,Wang, Bin
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supporting information
p. 6344 - 6347
(2017/12/08)
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- PYRAZOLONE DERIVATIVES AS NITROXYL DONORS
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The disclosed subject matter provides pyrazolone derivative compounds, pharmaceutical compositions comprising such compounds, kits comprising such compounds, and methods of using such compounds or pharmaceutical compositions. In particular, the disclosed subject matter provides methods of using such compounds or pharmaceutical compositions for treating heart failure.
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Page/Page column 254; 255
(2016/01/29)
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- A one-pot copper(II)-catalyzed tandem synthesis of 2-substituted pyrrolo[1,2-b]pyridazin-4(1H)-ones
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A one-pot copper(II)-catalyzed tandem synthesis of 2-substituted pyrrolo[1,2-b]pyridazin-4(1H)-ones from N-aminopyrroles was developed. This tandem reaction involves a Conrad-Limpach-type reaction, including the thermal condensation of N-aminopyrroles with the carbonyl group of β-oxo esters followed by the cyclization of Schiff base intermediates. Compared to the traditional Conrad-Limpach quinoline synthesis, we herein successfully applied copper(II) as a catalyst in this transformation to furnish 2-substituted pyrrolo[1,2-b]pyridazin-4(1H)-ones for the first time. Most of the substrates bearing electron-donating (EDG) and electron-withdrawing (EWG) groups worked well with this procedure. The corresponding products could be converted directly into diverse pyrrolo[1,2-b]pyridazine for drug discovery and materials science. A copper(II)-catalyzed tandem synthesis of 2-substituted pyrrolo[1,2-b]pyridazin-4(1H)-ones from N-aminopyrroles was developed, and the corresponding products could be converted directly into diverse pyrrolo[1,2-b]pyridazine for drug discovery and materials science.
- Tan, Cun,Xiang, Haoyue,He, Qian,Yang, Chunhao
-
supporting information
p. 3656 - 3660
(2015/06/16)
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- Access to β-keto esters by palladium-catalyzed carbonylative coupling of aryl halides with monoester potassium malonates
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New tricks for an old dog: The Pd-catalyzed carbonylative α-arylation of monoethyl potassium malonates with aryl bromides and reactive aryl chlorides provides a simple and direct route to aryl β-ketoesters. Because only stoichiometric amounts of carbon monoxide are employed, the method is ideal for the introduction of carbon isotopes into more complex structures. Copyright
- Korsager, Signe,Nielsen, Dennis U.,Taaning, Rolf H.,Skrydstrup, Troels
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supporting information
p. 9763 - 9766
(2013/09/23)
-
- PYRAZOLOPYRIMIDINE JAK INHIBITOR COMPOUNDS AND METHODS
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The invention provides JAK kinase inhibitors of Formula Ia, enantiomers, diasteriomers or pharmaceutically acceptable salts thereof, wherein R1, R2, R7 and Z are defined herein, a pharmaceutical composition that includes a compound of Formula Ia and a pharmaceutically acceptable carrier, adjuvant or vehicle, and methods of treating or lessening the severity of a disease or condition responsive to the inhibition of a JAK kinase activity in a patient.
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Page/Page column 89
(2012/02/03)
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- Dynamic kinetic resolution in the asymmetrie synthesis of β-amino acids by organocatalytic reduction of enamines with trichlorosilane
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A new methodology based on the organocatalytic asymmetric hydrosilylation of enamines that allows a direct access to a range of β3 and β2.3-amino acid derivatives was presented. The results show a successful reduction of aromatic substrates, a sterically more hindered ortho-substituted derivatives, and the thiophenyl analogue exhibiting lower reactivity. Fast enamine-imine equilibration is crucial as imines are chiral but racemic, while α-alkyl β-amino acids can be accessed by the symmetrical Mannich reaction. The α-alkyl derivatives have relative and absolute configuration due to their reduction with LiAlH4 into a known amino alcohols. Predominant formation of the anti isomer in 3o is consistent with conformation of the imine intermediate in the catalytic reduction.
- Malkov, Andrei V.,Stoncius, Sigitas,Vrankova, Kvetoslava,Arndt, Matthias,Kocovsky, Pavel
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supporting information; experimental part
p. 8082 - 8085
(2009/09/29)
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- DBU-catalyzed condensation of acyldiazomethanes to aldehydes in water and a new approach to ethyl β-hydroxy α-arylacrylates
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DBU-catalyzed condensation of ethyl diazoacetate (EDA) with aldehydes in pure water afforded corresponding β-hydroxy α-diazo carbonyl compounds. The β-hydroxy group of the products was further converted into β-siloxy group. The Rh(II)-catalyzed reaction of the β-aryl β-siloxy α-diazo carbonyl compounds gave 1,2-aryl shift products predominantly. The three-step transformation constitutes an efficient synthesis of ethyl β-hydroxy α-arylacrylates.
- Xiao, Fengping,Liu, Yu,Wang, Jianbo
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p. 1147 - 1149
(2007/10/03)
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- CuSO4-catalyzed diazo decomposition in water: a practical synthesis of β-keto esters
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CuSO4 was found to be an efficient catalyst for the diazo decomposition of β-hydroxy α-diazoesters in water. 1,2-H shift occurred efficiently to give β-keto esters in high yields. No O-H bond insertion products were identified.
- Liao, Mingyi,Wang, Jianbo
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p. 8859 - 8861
(2007/10/03)
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- Synthesis and herbicidal evaluation of novel 3-[(α-hydroxy- substituted)benzylidene]pyrrolidine-2,4-diones
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A series of 3-[(α-hydroxy-substituted) benzylidene]pyrrolidine-2,4- dione derivatives were synthesized as candidate herbicides by reacting different aroyl acetates with N-substituted glycine esters. The new compounds were identified by 1H NMR spectroscopy and elemental analyses. Their herbicidal activities were evaluated. Some compounds exhibited excellent herbicidal activities at a dose of 187.5 g/ha. A suitable electron-donating substituent at the 2- and/or 4-position of the phenyl ring was essential for high herbicidal activity, a result that has not been reported before. It was also found that the title compound's structure-activity relationships were different from those of other similar kinds of earlier compounds, a result that may depend on the enol structure difference.
- Zhu, Youquan,Zou, Xiaomao,Hu, Fangzhong,Yao, Changsheng,Liu, Bin,Yang, Huazheng
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p. 9566 - 9570
(2007/10/03)
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- Photochemical preparation of highly functionalized 1-indanones
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A series of o-alkylphenyl alkyl ketones 1 were synthesized by different methods. The presence of a leaving group X adjacent to the carbonyl group is the special peculiarity of these ketones. Upon irradiation the keto carbonyl group of these compounds undergoes an n-π* excitation followed by a 1,5-hydrogen migration from the o-alkyl substituent to the carbonyl oxygen atom. The thus formed 1,4-diradicals are subject to a very rapid elimination of acid HX, giving 1,5-diradicals. We called this process spin center shift. After intersystem crossing these diradicals cyclize to 1-indanones 20 in good yields. Depending on the solvent and on substituents, o-alkoxyalkyl ketones 22 or benzo-[c]furanes 21 are obtained as byproducts. The mechanism of the cyclization was elucidated by quantum chemical calculations and kinetic measurements.
- Wessig, Pablo,Glombitza, Clemens,Mueller, Gunnar,Teubner, Janek
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p. 7582 - 7591
(2007/10/03)
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- Acid-catalyzed reactions of aromatic aldehydes with ethyl diazoacetate: An investigation on the synthesis of 3-hydroxy-2-arylacrylic acid ethyl esters
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Several commercial Lewis acids, including those of the Bronsted type, specifically HBF4·OEt2, are able to catalyze the reaction between aromatic aldehydes and ethyl diazoacetate to produce 3-hydroxy-2-arylacrylic acid ethyl esters and 3-oxo-3-arylpropanoic acid ethyl esters. Reactions catalyzed by the iron Lewis acid [(η5-C 5H5)Fe+(CO)2(THF)]BF 4- (i.e., 1) have the best yields and greatest ratio of 3-hydroxy-2-arylacrylic acid ethyl ester. The product distribution of 1 is not affected in the presence of Proton Sponge, but is dependent on temperature and the nature of the substrate aldehyde, whereas the activity of HBF 4-OEt2 is affected by the presence of Proton Sponge and is reactive at temperatures as low as -78 °C. Consequently, both 1 and HBF4·OEt2 are valuable catalysts in producing important 3-hydroxy-2-arylacrylic acid ethyl esters as precursors to biologically active compounds.
- Dudley, Matthew E.,Morshed, Monzur,Brennan, Courtney L.,Islam, M. Shahidul,Ahmad, M. Syarhabil,Atuu, Mary-Rose,Branstetter, Bryan,Hossain, M. Mahmun
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p. 7599 - 7608
(2007/10/03)
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- PYRAZOLOPYRIMIDINES AS CYCLIN DEPENDENT KINASE INHIBITORS
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In its many embodiments, the present invention provides a novel class of pyrazolo[1,5-a]pyrimidine compounds as inhibitors of cyclin dependent kinases, methods of preparing such compounds, pharmaceutical compositions containing one or more such compounds, methods of preparing pharmaceutical formulations comprising one or more such compounds, and methods of treatment, prevention, inhibition, or amelioration of one or more diseases associated with the CDKs using such compounds or pharmaceutical compositions.
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Page/Page column 33
(2008/06/13)
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- PYRAZOLOPYRIMIDINES AS CYCLIN DEPENDENT KINASE INHIBITORS
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In its many embodiments, the present invention provides a novel class of pyrazolo[1,5-a]pyrimidine compounds as inhibitors of cyclin dependent kinases, methods of preparing such compounds, pharmaceutical compositions containing one or more such compounds, methods of preparing pharmaceutical formulations comprising one or more such compounds, and methods of treatment, prevention, inhibition, or amelioration of one or more diseases associated with the CDKs using such compounds or pharmaceutical compositions.
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- Pyrolysis of quinoline-3,4-dicarboxylic anhydrides bearing 2-phenyl, 2-benzyl and 2-o-tolyl substituents: Formation of products of carbene insertion and addition
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Flash vacuum pyrolysis of 2-phenylquinoline-3,4-dicarboxylic anhydride at 800°/0.06 mm gave indeno[1,2-b]indole (30-40%), which readily added nucleophiles Y- at C-10 to give 5,10-dihydro derivatives (Y=H, Me, Ph, NEt2, OMe, CH(COOMe)2 and CMe2NO2). Similar pyrolysis of the 2-benzylquinoline anhydride gave a 1:2 mixture of the (expected) linear 5H-benzo[b]carbazole and the (unexpected) angular 7H-benzo[c]carbazole. The isomeric 2-o-tolylquinoline anhydride on similar pyrolysis gave mainly 11H-benzo[a]carbazole (85%), isomeric benzocarbazoles (4%) and 11H-indeno[1,2-b]quinoline (2.6%). Most of these products are probably derived from exocyclic carbenes formed by aryne-carbene equilibration, but the last compound may be formed by direct aryne-methyl interaction.
- Brown,Coulston,Eastwood,Moffat
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p. 7763 - 7774
(2007/10/02)
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- Photochemical Cyclization of o-Methylphenyl 1,3-Diketones
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The photochemistry of five 1,3-dicarbonyl compounds, substituted at the 1-position with an o-methylphenyl group, has been investigated.Compounds 5a-c cyclize upon irradiation to give tetralones 6a and 6c and octahydroanthracene derivative 6b, respectively.Compounds 5d and 5e do not form similar photoproducts.Diketone 5c is the most efficient in this reaction, indicating that the reaction probably occurs via the keto tautomer.A mechanism involving initial γ-hydrogen abstraction followed by interception of the resulting 1,4-biradical by the second carbonyl group is proposed.
- Hornback, Joseph M.,Poundstone, Melani L.,Vadlamani, Bhanumathi,Graham, Susan M.,Gabay, Julie,Patton, Shelly T.
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p. 5597 - 5601
(2007/10/02)
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- SYNTHESIS OF ETHYL ortho-SUBSTITUTED BENZOYLACETATES AND INVESTIGATION OF THE INFLUENCE OF ortho-SUBSTITUENTS ON KETO-ENOL TAUTOMERISM AND MS FRAGMENTATION BEHAVIOUR
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A series of seven ethyl 2-acetyl-(2-substituted benzoyl)acetates II-VIII was synthesized, together with their parent compound I, from the corresponding acid chlorides.The tautomerism of these β-tricarbonyl compounds in tetrachloromethane was studied by 1H NMR spectroscopy and former results concerning this problem were critically evaluated.A further series of seven ortho-substituted ethyl benzoylacetates X-XV and XVII was obtained from the corresponding precursors II-VIII.The keto-enol tautomerism of these β-keto esters was studied by 1H NMR in different solventsand compared with ethyl benzoylacetate IX as standard.Differences caused by the ortho-substituents are discussed.Investigation of the mass spectrometric fragmentation of the β-keto esters IX-XV and XVII showed both common fragmentation pathways due to the same substance class and typical differences in relative intensities according to the nature of the ortho-substituent.
- Sicker, Dieter,Mann, Gerhard
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p. 839 - 850
(2007/10/02)
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- ELECTROOXIDATION OF 2-ARYLFURANS
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Electrochemical methoxylation of 2-phenylfuran (I) and 2-(4-nitrophenyl)furan (VI) proceeded anomalously, affording 5-methoxy-2-phenylfuran (XI) and 5-methoxy-2-(4-nitrophenyl)furan (XIII), respectively. 2-Phenyl-5-methylfuran (II) and methyl-2-(2-methylphenyl)-3-furoate (VIII) behaved normally giving the respective 2,5-dimethoxy-2,5-dihydrofuran derivatives XII and XIV.The suggested ECNECB mechanism of the anomalous methoxylation was confirmed by methoxylation of compound II, in which the methyl group hinders the last CB step, and also of compound VIII in whichthe aromaticity is suppresed by forced deviation from planarity.Forced deviation from planarity was moreover studied also on 2-(4-methylphenyl)furan (III), 5-methyl-2-(2-methylphenyl)furan (IV) and 3,5-dimethyl-2-(2-methylphenyl)furan (V) as model compounds.For all the derivatives the INDO charges were calculated and correlated with the 1H- and 13C-NMR spectra.The experimental electronic spectra were correlated with the theoretical ones (INDO-S-CI).All results obtained confirm the suggested mechanism.
- Janda, Miroslav,Srogl, Jan,Dvorakova, Hana,Dvorak, Dalimil,Stibor, Ivan
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p. 906 - 916
(2007/10/02)
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