22253-11-8Relevant academic research and scientific papers
Photochemical Coupling between Indene and Nitroarenes
D'Auria, Maurizio
, p. 633 - 636 (1994)
The photochemical reaction between indene and nitroarenes gave an unusual reaction performing the substitution of the nitro group.
Merging Halogen-Atom Transfer (XAT) and Copper Catalysis for the Modular Suzuki-Miyaura-Type Cross-Coupling of Alkyl Iodides and Organoborons
Zhang, Zhenhua,Górski, Bartosz,Leonori, Daniele
, p. 1986 - 1992 (2022/02/01)
We report here a mechanistically distinct approach to achieve Suzuki-Miyaura-type cross-couplings between alkyl iodides and aryl organoborons. This process requires a copper catalyst but, in contrast with previous approaches based on palladium and nickel
Electrochemically Enabled, Nickel-Catalyzed Dehydroxylative Cross-Coupling of Alcohols with Aryl Halides
Li, Zijian,Sun, Wenxuan,Wang, Xianxu,Li, Luyang,Zhang, Yong,Li, Chao
supporting information, p. 3536 - 3543 (2021/03/08)
As alcohols are ubiquitous throughout chemical science, this functional group represents a highly attractive starting material for forging new C-C bonds. Here, we demonstrate that the combination of anodic preparation of the alkoxy triphenylphosphonium ion and nickel-catalyzed cathodic reductive cross-coupling provides an efficient method to construct C(sp2)-C(sp3) bonds, in which free alcohols and aryl bromides - both readily available chemicals - can be directly used as coupling partners. This nickel-catalyzed paired electrolysis reaction features a broad substrate scope bearing a wide gamut of functionalities, which was illustrated by the late-stage arylation of several structurally complex natural products and pharmaceuticals.
Birch-Type Photoreduction of Arenes and Heteroarenes by Sensitized Electron Transfer
Chatterjee, Anamitra,K?nig, Burkhard
supporting information, p. 14289 - 14294 (2019/08/30)
The direct reduction of arenes and heteroarenes by visible-light irradiation remains challenging, as the energy of a single photon is not sufficient for breaking aromatic stabilization. Shown herein is that the energy accumulation of two visible-light photons allows the dearomatization of arenes and heteroarenes. Mechanistic investigations confirm that the combination of energy-transfer and electron-transfer processes generates an arene radical anion, which is subsequently trapped by hydrogen-atom transfer and finally protonated to form the dearomatized product. The photoreduction converts planar aromatic feedstock compounds into molecular skeletons that are of use in organic synthesis.
Cyclopropanation with gold(I) carbenes by retro-Buchner reaction from cycloheptatrienes
Solorio-Alvarado, César R.,Wang, Yahui,Echavarren, Antonio M.
, p. 11952 - 11955 (2011/10/04)
Cationic gold(I) promotes the retro-Buchner reaction of 7-substituted 1,3,5-cycloheptatrienes, leading to gold(I) carbenes that cyclopropanate alkenes.
Molecular conformations of jet-cooled 2-methylindan and 2-phenylindan
Hamza, Abdulhamid
, p. 939 - 945 (2011/11/01)
The molecular conformations of jet-cooled 2-methylindan (2MI) and 2-phenylindan (2PI) have been studied using resonant-enhanced two-photon ionization spectroscopy in combination with ab initio calculations. Both axial (2MIax) and equatorial (2MIeq) conformers of 2MI have been observed. A 2MIeq/2MIax conformer ratio of 2.3 was estimated at 298 K, leading to the energy difference, of 0.49 kcal/mol. Ab initio calculations predicted three stable conformers of 2PI: Two equatorial conformers (2PIeq0 and 2PIeq90), and one axial conformer (2PIax). Only the axial conformer of 2PI (2PIax) was experimentally observed. The indan ring of 2PIax is slightly more planar than the indan rings of the two equatorial conformers of 2PI because of the intramolecular Csp2-H/π interactions in 2PIax. The equatorial conformers of 2PI relax to the more stable axial conformer because of the high pre-expansion temperature (383 K), and relatively low barrier (1.68 kcal/mol) to axial-equatorial interconversion. The barrier (2.33 kcal/mol) to axial-equatorial interconversion in 2MI is high enough to prevent conformational relaxation at the pre-expansion temperature of 298 K. Intramolecular C-H/π interactions are found to be more important in determining the conformational preference of 2PI than 2MI; this can be attributed to the higher acidity of the Csp2-H bond than that of Csp3-H bond.
Reactivity of functionalized arylcarbenes. 2-Phenylethyl side chains and hetero analogues
Kirmse, Wolfgang,Konrad, Wolfgang,Oezkir, Ismail S.
, p. 9935 - 9964 (2007/10/03)
Phenylcarbenes with -X-CH2Ph and -CH2-X-Ph (X = CH2, O, SiMe2) groups in the ortho position were generated thermally and photolytically from diazo or tosylhydrazone precursors. Stereorandom insertion reactions with β-C-H bonds were observed, pointing to a triplet abstraction-recombination mechanism. Large kinetic and stereochemical deuterium isotope effects support this notion. The ample formation of benzocyclobutenes from 2-CH2-X-Ph substrates is due to insertion of the carbenes into ArCH2-X bonds. Addition to the terminal phenyl groups competes with C-H and C-X insertion. The results of benzophenone sensitization and of trapping with methanol suggest that the intramolecular reactions of functionalized arylcarbenes proceed, at best, competitively with spin inversion.
Synthesis and nuclear magnetic resonance spectroscopy of indane structures: indanes mono- and disubstituted in the pentagonal ring
Alesso, Elba N.,Tombari, Dora G.,Ibanez, Adriana F.,Iglesias, Graciela Y. Moltrasio
, p. 1166 - 1170 (2007/10/02)
Indanes monosubstituted and 1,2- and 1,3-disubstituted in the pentagonal ring were synthesized, and configurations were assigned to the 1,2-disubstituted compounds by means of nuclear magnetic resonance spectroscopy.Key words: mono- and disubstituted indanes, conformation, configuration, 1H and 13C NMR, synthesis.
The SRN1 Photoarylation of Indenyl Anions
Tolbert, Laren M.,Siddiqui, Shahabuddin
, p. 1744 - 1751 (2007/10/02)
Irradiation of Me2SO solutions of indenyl anion and its phenylated analogues in the presence of bromobenzene produces the higher phenylated indenes.Thus indenyl anion (1b) yields 3-phenylindene (3a), 1-phenylindenyl anion (3b) yields 1,3- and 1,1-diphenylindene, 2-phenylindenyl anion (2b) produces 2,3-diphenylindene, 1,3-diphenylindenyl anion (6b) produces 1,1,3- and 1,2,3-triphenylindene, and 1,2-diphenylindenyl anion (5b) produces 1,2,3-triphenylindene (8).In liquid ammonia and tetrahydrofuran more complex reaction pathways are observed.The regiochemistry of phenylation is attributed to radical attack at the most basic site, in accord with a previously published model.
Hydrosulfite Reduction of N-Nitroso-1,2,3,4-tetrahydroisoquinolines and Oxidation of N-Amino-1,2,3,4-tetrahydroisoquinolines
Powell, Burwell F.,Overberger, C. G.,Anselme, J.-P.
, p. 121 - 128 (2007/10/02)
The sodium hydrosulfite reduction of N-nitroso-1,2,3,4,-tetrahydroisoquinolines (5) does not result in the loss of nitrogen and leads to the corresponding hydrazine 6 which upon oxidation with mercuric oxide in ethanol at 62 deg gives the hexahydrotetrazine 7 in 39percent yield.Treatment of the n-tosyl derivative of 6 with base affords 7 in nearly quantitative yield.Oxidation of 6 in 1-butanol at 95 deg results in the formation of a complex product mixture from which only one component, 1,1'-azobis-3,4-dihydroisoquinoline (8) could be isolated.Surprisingly the sodium hydrosulfite reduction of 2-nitroso-3-phenyl-1,2,3,4-tetrahydroisoquinoline (15) also failed to proceed with loss of nitrogen and yields the corresponding hydrazine 16.However, 16 was cleanly oxidized by mercuric oxide in ethanol at 62 deg with concurrent elimination of nitrogen to afford 2-phenylindane in 75percent yield.Possible rationalizations for these results are presented.
