Search results for "craft"
showing 10 items of 369 documents
Catalytic enantioselective Friedel–Crafts alkylation at the 2-position of indole with simple enones
2007
Abstract A procedure for the enantioselective alkylation of indole at the 2-position with simple non-chelating enones is described for the first time. Reaction between 4,7-dihydroindole and enones in the presence of zirconium(IV)–BINOL complexes, followed by a p -benzoquinone oxidation gives indoles alkylated at the 2-position with good yields and moderate enantioselectivities.
ChemInform Abstract: Enantioselective Friedel-Crafts Alkylation of Indoles with (E)-1-Aryl-4-benzyloxybut-2-en-1-ones Catalyzed by an (R)-3,3′-Br2BIN…
2013
A highly enantioselective Friedel–Crafts reaction of unprotected indoles with (E)-1-aryl-4-benzyloxybut-2-en-1-ones catalyzed by a new chiral [Hf{(R)-3,3′-Br2-BINOL}(OtBu)2]2 complex has been developed to functionalize the C-3 position of the indole nucleus with a side chain bearing a 1,4-difunctionalized moiety and a benzylic stereogenic center. The reaction proceeds in good to excellent yields and excellent enantioselectivities (up to 97 % ee). The usefulness of this approach was illustrated with the synthesis of a tryptophol derivative.
Enantioselective Friedel-Crafts Alkylation of Indoles with (E)-1-Aryl-4-benzyloxybut-2-en-1-ones Catalyzed by an (R)-3,3′-Br2BINOLate-Hafnium(IV) Com…
2013
A highly enantioselective Friedel–Crafts reaction of unprotected indoles with (E)-1-aryl-4-benzyloxybut-2-en-1-ones catalyzed by a new chiral [Hf{(R)-3,3′-Br2-BINOL}(OtBu)2]2 complex has been developed to functionalize the C-3 position of the indole nucleus with a side chain bearing a 1,4-difunctionalized moiety and a benzylic stereogenic center. The reaction proceeds in good to excellent yields and excellent enantioselectivities (up to 97 % ee). The usefulness of this approach was illustrated with the synthesis of a tryptophol derivative.
Catalytic Asymmetric Friedel–Crafts Alkylations in Total Synthesis
2009
Synthesis of Functionalized Indoles with a Trifluoromethy-Substituted Stereogenic Tertiary Carbon Atom Through an Enantioselective Friedel-Crafts Alk…
2010
[EN] Chiral complexes of BINOL-based ligands with zirconium tert-butoxide catalyze the Friedel-Crafts alkylation reaction of indoles with beta-trifluoromethyl-alpha,beta-unsaturated ketones to give functionalized indoles with an asymmetric tertiary carbon center attached to a trifluoromethyl group. The reaction can be applied to a large number of substituted alpha-trifluoromethyl enones and substituted indoles. The expected products were obtained with good yields and ees of up to 99%.
Organocatalytic Enantioselective Friedel–Crafts Aminoalkylation of Indoles in the Carbocyclic Ring
2016
The first general catalytic method for the, so far elusive, enantioselective Friedel−Crafts functionalization of indoles in the carbocyclic ring is presented. This transformation contrasts with the usual tendency of these heterocycles to react at the azole ring. For this purpose, the four regioisomeric hydroxy carbocyclic-substituted indoles were reacted with several isatinderived ketimines, using a Cinchona alkaloid-based squaramide, in a low 0.5−5 mol % catalyst loading, as a bifunctional catalyst. This methodology allows the functionalization of indoles in every position of the carbocyclic ring in a regio- and enantioselective fashion, by switching only the position of the hydroxy group …
QCD resummation effects in forward J/ψ and very backward jet inclusive production at the LHC
2017
´ We propose and study the inclusive production of a forward J/ψ and a very backward jet at the LHC as an observable to reveal high-energy resummation effects à la BFKL. Our different predictions are based on the various existing mechanisms to describe the production of the J/ψ, namely, NRQCD singlet and octet contributions, and the color evaporation model. © 2017 Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). Peer reviewed
New development opportunities for the craft brewing segment: the case study of a micro-malthouse
2017
In Italy in the past few years, the number of small breweries penetrating the craft beer sector has grown exponentially. Craft producers intend to give a strong added value and a local character to their production in different ways. One of these is the use of malt derived from small batches of local cereals and pseudo cereals. The aim of this study is the assessment of investment profitability, through a cost-benefit analysis (CBA), for a compact and a modular micro-malting plant in Sicily (Southern Italy). The CBA for a micro-malthouse was carried out considering both installation and operating costs. Net present value (NPV), discounted benefit-cost ratio (DBCR) and internal rate of retur…
Organocatalytic Enantioselective Synthesis of α-Hydroxyketones through a Friedel−Crafts Reaction of Naphthols and Activated Phenols with Aryl- and Al…
2016
[EN] An efficient organocatalytic asymmetric synthesis of alpha-hydroxyketones has been developed. Quinine-derived thiourea catalyzed the enantioselective Friedel Crafts alkylation of naphthols and activated phenols with aryl- and alkylglyoxal hydrates, providing the corresponding chiral alpha-hydroxyketones with high yields (up to 97%) and excellent enantioselectivities (up to 99% ee).
Digitālo rīku izmantošana vēstures mācību satura apguves veicināšanai 7. klasē
2022
Diplomdarba temats: “Digitālo rīku izmantošana vēstures mācību satura apguves veicināšanai 7. klasē” (Use of digital tools to promote the acquisition of history curriculum in 7th grade). Izglītības iestāžu uzdevums ir sagatavot skolēnus reālai pasaulei un nekas nav tik aktuāls 21. gadsimta kā digitālo prasmju attīstīšana. Mācot skolēnus lietpratīgi un pareizi lietot digitālos rīkus vēstures priekšmeta ietvaros dod skolēniem pārnesamās prasmes kuras ir iespējams izmantot ārpus skolas un/vai citos priekšmetos, veidojot caurviju prasmi. Vadoties pēc Skola 2030 mērķiem ieviest izmaiņas Latvijas izglītības sistēmā ir nopietni jāaizdomājas par šīs jomas digitalizēšanu, padarot to vēl aktuālāku un…