13672-07-6Relevant articles and documents
Synthesis of phosphonate derivatives of 2,3-dihydroindene
Prokopowicz, Monika,M?ynarz, Piotr,Kafarski, Pawe?
, p. 7314 - 7317 (2009)
Simple and convenient procedures for the synthesis of derivatives of 2,3-dihydroinden-2-ylphosphonic acid are developed. The reaction strategies utilize both functionalization of the already existing 2,3-dihydroindene skeleton and an annulation reaction starting from readily available o-disubstituted benzene derivatives.
One-pot synthesis of 4-alkoxybenzo[c]thiophenes
Akbarzadeh, Tahmineh,Shafiee, Abbas
, p. 1455 - 1462 (2004)
The reaction of N-bromosuccinimide with 4,5,6,7-tetrahydrobenzo[c]thiophen-4-ones in the presence of 2,2′-azo-bis-isobutyronitrile followed by heating under reflux with different alcohols produces 4-alkoxybenzo[c]thiophenes in good yield.
Non-linear, cata-Condensed, Polycyclic Aromatic Hydrocarbon Materials: A Generic Approach and Physical Properties
Haire, Barnaby T.,Heard, Kane W. J.,Little, Mark S.,Parry, Adam V. S.,Raftery, James,Quayle, Peter,Yeates, Stephen G.
, p. 9970 - 9974 (2015)
A generic approach to the regiospecific synthesis of halogenated polycyclic aromatics is made possible by the one- or two-directional benzannulation reactions of readily available (ortho-allylaryl)trichloroacetates (the "BHQ" reaction). Palladium-catalyse
A Method for the Catalytic Enantioselective Synthesis of Chiral α-Azido and α-Amino Ketones from Racemic α-Bromo Ketones, and Its Generalization to the Formation of Bonds to C, O, and S
Da Silva Gomes, Roberto,Corey
, p. 20058 - 20061 (2019)
A new and practical method has been developed for the transformation of racemic α-bromo ketones to chiral α-azido and α-amino ketones with high enantioselectivity using phase transfer, ion-pair mediated reactions with a recoverable chiral quaternary salt (10 mol %) as catalyst in fluorobenzene-water. The process has been generalized to a variety of other attachments including of C, O, S, and NHR.
Studies on bromination of active methylene by a mixture of hydrobromic acid and hydrogen peroxide (or TBHP)
Tillu, Vasudha H.,Shinde, Popat D.,Bedekar, Ashutosh V.,Wakharkar, Radhika D.
, p. 1399 - 1403 (2003)
Studies on bromination of active methylene with a mixture of hydrogen peroxide or tert-butylhydroperoxide (TBHP) and hydrobromic acid are discussed. Substituted acetophenones, benzocyclic ketones provide α-bromo-keto compounds in high yields under this re
Acridine Orange Hemi(Zinc Chloride) Salt as a Lewis Acid-Photoredox Hybrid Catalyst for the Generation of α-Carbonyl Radicals
Das, Sanju,Mandal, Tanumoy,De Sarkar, Suman
supporting information, p. 755 - 765 (2021/12/10)
A readily accessible organic-inorganic hybrid catalyst is reported for the reductive fragmentation of α-halocarbonyl compounds. The robust hybrid catalyst is a self-stabilizing combination of ZnCl2 Lewis acid and acridine orange as the photoactive organic dye. Mechanistic specifics of this hybrid catalyst have been studied in detail using both photophysical and electrochemical experiments. A systematic study enabled the discovery of the appropriate Lewis acid for the effective LUMO stabilization of α-halocarbonyl compounds and thereby lowering of reduction potential within the range of a standard organic dye. This strategy resolves the issues like dehalogenative hydrogenation or homo-coupling of alkyl radicals by guiding the photoredox cycle through an oxidative quenching pathway. The cooperativity between the photoactive organic dye and the Lewis acid counterparts empowers functionalization with a wide range of coupling partners through efficient and controlled generation of alkyl radicals and serves as an appropriate alternative to the expensive late transition metal-based photocatalysts. To demonstrate the application potential of this cooperative catalytic system, four different synthetic transformations of α-carbonyl bromides were explored with broad substrate scopes.
Highly Deformed o-Carborane Functionalised Non-linear Polycyclic Aromatics with Exceptionally Long C?C Bonds
Marsh, Adam V.,Little, Mark,Cheetham, Nathan J.,Dyson, Matthew J.,Bidwell, Matthew,White, Andrew J. P.,Warriner, Colin N.,Swain, Anthony C.,McCulloch, Iain,Stavrinou, Paul N.,Heeney, Martin
supporting information, p. 1970 - 1975 (2020/12/25)
The effect of substituting o-carborane into the most sterically hindered positions of phenanthrene and benzo(k)tetraphene is reported. Synthesised via a Bull–Hutchings–Quayle benzannulation, the crystal structures of these non-linear acenes exhibited the highest aromatic deformation parameters observed for any reported carborane compound to date, and among the largest carboranyl C?C bond length of all organo-substituted o-carboranes. Photoluminescence studies of these compounds demonstrated efficient intramolecular charge-transfer, leading to aggregation induced emission properties. Additionally, an unusual low-energy excimer was observed for the phenanthryl compound. These are two new members of the family of carborane-functionalised non-linear acenes, notable for their peculiar structures and multi-luminescent properties.
Annulation reaction of cyclic pyridinium ylides with: In situ generated azoalkenes for the construction of spirocyclic skeletons
Quan, Bao-Xue,Yuan, Wei-Cheng,Zhang, Ming-Liang,Zhang, Xiao-Mei,Zhao, Jian-Qiang,Zhou, Ming-Qiang,Zhuo, Jun-Rui
supporting information, p. 1886 - 1891 (2020/03/23)
Two new types of cyclic pyridinium ylides were designed and further used in reactions with azoalkenes to access structurally diverse spirocyclic compounds. A range of spiropyrazoline oxindoles could be smoothly obtained in up to 99% yield via a [4 + 1] annulation process with oxindole 3-pyridinium ylides as C1 synthons. Similarly, a series of spiropyrazoline indanones could be prepared with indanone 2-pyridinium ylides as C1 synthons. This work represents the first example of cyclic pyridinium ylides as C1 synthons for the efficient construction of spirocyclic compounds.
Azologization and repurposing of a hetero-stilbene-based kinase inhibitor: Towards the design of photoswitchable sirtuin inhibitors
Grathwol, Christoph W.,W?ssner, Nathalie,Swyter, S?ren,Smith, Adam C.,Tapavicza, Enrico,Hofstetter, Robert K.,Bodtke, Anja,Jung, Manfred,Link, Andreas
supporting information, p. 2170 - 2183 (2019/09/30)
The use of light as an external trigger to change ligand shape and as a result its bioactivity, allows the probing of pharmacologically relevant systems with spatiotemporal resolution. A hetero-stilbene lead resulting from the screening of a compound that was originally designed as kinase inhibitor served as a starting point for the design of photoswitchable sirtuin inhibitors. Because the original stilbenoid structure exerted unfavourable photochemical characteristics it was remodelled to its heteroarylic diazeno analogue. By this intramolecular azologization, the shape of the molecule was left unaltered, whereas the photoswitching ability was improved. As anticipated, the highly analogous compound showed similar activity in its thermodynamically stable stretched-out (E)-form. Irradiation of this isomer triggers isomerisation to the long-lived (Z)-configuration with a bent geometry causing a considerably shorter end‐to‐end distance. The resulting affinity shifts are intended to enable real‐time photomodulation of sirtuins in vitro.
The Electrophilic Fluorination of Enol Esters Using SelectFluor: A Polar Two-Electron Process
Wood, Susanna H.,Etridge, Stephen,Kennedy, Alan R.,Percy, Jonathan M.,Nelson, David J.
supporting information, p. 5574 - 5585 (2019/03/21)
The reaction of enol esters with SelectFluor is facile and leads to the corresponding α-fluoroketones under mild conditions and, as a result, this route is commonly employed for the synthesis of medicinally important compounds such as fluorinated steroids. However, despite the use of this methodology in synthesis, the mechanism of this reaction and the influence of structure on reactivity are unclear. A rigorous mechanistic study of the fluorination of these substrates is presented, informed primarily by detailed and robust kinetic experiments. The results of this study implicate a polar two-electron process via an oxygen-stabilised carbenium species, rather than a single-electron process involving radical intermediates. The structure–reactivity relationships revealed here will assist synthetic chemists in deploying this type of methodology in the syntheses of α-fluoroketones.