cas 2546-56-7, 4-Chloro-3-fluoropyridine | Articles data

Articles about 2546-56-7Total 6 be found

Deaminative chlorination of aminoheterocycles
Selective modification of heteroatom-containing aromatic structures is in high demand as it permits rapid evaluation of molecular complexity in advanced intermediates. Inspired by the selectivity of deaminases in nature, herein we present a simple methodology that enables the NH2 groups in aminoheterocycles to be conceived as masked modification handles. With the aid of a simple pyrylium reagent and a cheap chloride source, C(sp2)?NH2 can be converted into C(sp2)?Cl bonds. The method is characterized by its wide functional group tolerance and substrate scope, allowing the modification of >20 different classes of heteroaromatic motifs (five- and six-membered heterocycles), bearing numerous sensitive motifs. The facile conversion of NH2 into Cl in a late-stage fashion enables practitioners to apply Sandmeyer- and Vilsmeier-type transforms without the burden of explosive and unsafe diazonium salts, stoichiometric transition metals or highly oxidizing and unselective chlorinating agents. [Figure not available: see fulltext.]
Ghiazza, Clément,Faber, Teresa,Gómez-Palomino, Alejandro,Cornella, Josep
p. 78 - 84
(2021/12/23)

Thorpe–Ingold Effect in Branch-Selective Alkylation of Unactivated Aryl Fluorides
Presented herein is a general protocol for the alkylation of simple aryl fluorides with unbiased secondary Grignard reagents by means of nickel catalysis. This study revealed a general Thorpe–Ingold effect in the ligand backbone which confers a high degree of selectivity for the secondary carbon center in the C?C coupling event. This protocol is characterized by mild reaction conditions, robustness, and simplicity. Both electron-rich and electron-deficient aryl fluorides are suitable candidates in this transformation. Equally amenable are a variety of heterocycles, permitting the coupling without over alkylation at the electrophilic sites.
O'Neill, Matthew J.,Riesebeck, Tim,Cornella, Josep
supporting information
p. 9103 - 9107
(2018/07/24)

HETEROCYCLIC COMPOUND AND PHARMACEUTICAL COMPOSITION COMPRISING SAME
The invention relates to a novel heterocyclic compound inhibiting a cyclin-dependent kinase (CDK) and a pharmaceutical composition comprising the same as an effective ingredient. The heterocyclic compound according to the present invention or pharmaceutically acceptable salt thereof can be effectively used in treating or preventing cancers, degenerative brain diseases, etc.
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Paragraph 0135; 0136

(2018/01/11)

Removal of fluorine from and introduction of fluorine into polyhalopyridines: An exercise in nucleophilic hetarenic substitution
Starting from six industrially available fluorinated pyridines, an expedient access to all three tetrafluoropyridines (2-4), all six trifluoropyridines (5-10), and the five non-commercial difluoropyridines (11-14 and 16) was developed. The methods employed for the selective removal of fluorine from polyfluoropyridines were the reduction by metals or complex hydrides and the site-selective replacement by hydrazine followed by dehydrogenation-dediazotation or dehydrochlorination-dediazotation. To introduce an extra fluorine atom, a suitable precursor was metalated and chlorinated before being subjected to a chlorine/ fluorine displacement process.
Bobbio, Carla,Rausis, Thierry,Schlosser, Manfred
p. 1903 - 1910
(2007/10/03)

PROCESS FOR THE PREPARATION OF N-AMINO SUBSTITUTED HETEROCYCLIC COMPOUNDS
An improved process for the preparation of N-amino nitrogen heterocyclic compounds is disclosed and claimed. In an ambodiment of this invention, a compound of the formula (VI) is prepared starting from the corresponding indole derivative by way of N-amination and subsequently forming an hydrazone by the reaction with a keto compound in a single step. Further reduction of the hydrazone and subsequent coupling with a pyridine compound affords the compound of formula VI or a suitable salt thereof.
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Page/Page column 32

(2008/06/13)

Converting core compounds into building blocks: The concept of regiochemically exhaustive functionalization
In a model study, 3-fluorophenol and 3-fluoropyridine were converted into the each time four possible carboxylic acids by passing through the corresponding organometallic intermediates. As an attempt to generalize the findings reveals, a restricted set of principles and methods suffices to cope with all standard scenarios. The most valuable and versatile tools for the regiochemically exhaustive functionalization of a great variety of substrate patterns are the optionally site-selective metalation (either by reagent/substrate matching or by peripheral coordination control), the use of activating or congesting protective groups and the basicity gradient-driven heavy halogen migration (followed by halogen/metal permutation). Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Marzi, Elena,Bobbio, Carla,Cottet, Fabrice,Schlosser, Manfred
p. 2116 - 2123
(2007/10/03)