106877-17-2Relevant articles and documents
The Stronger the Better: Donor Substituents Push Catalytic Activity of Molecular Chromium Olefin Polymerization Catalysts
Enders, Markus,Hansen, Helge-Boj,Wadepohl, Hubert
, p. 11084 - 11093 (2021)
The donor strength of bifunctional pyridine-cyclopentadienyl ligands was altered systematically by the introduction of donating groups in the para-position of the pyridine. In the resulting chromium complexes an almost linear correlation between donor str
Alcohols as alkylating agents in heteroarene C-H functionalization
Jin, Jian,MacMillan, David W. C.
, p. 87 - 90 (2015/09/15)
Redox processes and radical intermediates are found in many biochemical processes, including deoxyribonucleotide synthesis and oxidative DNA damage. One of the core principles underlying DNA biosynthesis is the radical-mediated elimination of H2O to deoxygenate ribonucleotides, an example of 'spin-centre shift', during which an alcohol C-O bond is cleaved, resulting in a carbon-centred radical intermediate. Although spin-centre shift is a well-understood biochemical process, it is underused by the synthetic organic chemistry community. We wondered whether it would be possible to take advantage of this naturally occurring process to accomplish mild, non-traditional alkylation reactions using alcohols as radical precursors. Because conventional radical-based alkylation methods require the use of stoichiometric oxidants, increased temperatures or peroxides, a mild protocol using simple and abundant alkylating agents would have considerable use in the synthesis of diversely functionalized pharmacophores. Here we describe the development of a dual catalytic alkylation of heteroarenes, using alcohols as mild alkylating reagents. This method represents the first, to our knowledge, broadly applicable use of unactivated alcohols as latent alkylating reagents, achieved via the successful merger of photoredox and hydrogen atom transfer catalysis. The value of this multi-catalytic protocol has been demonstrated through the late-stage functionalization of the medicinal agents, fasudil and milrinone.
Copper-mediated perfluoroalkylation of heteroaryl bromides with (phen)CuRF
Mormino, Michael G.,Fier, Patrick S.,Hartwig, John F.
, p. 1744 - 1747 (2014/04/17)
The attachment of perfluoroalkyl groups onto organic compounds has been a major synthetic goal over the past several decades. Previously, our group reported phenanthroline-ligated perfluoroalkyl copper reagents, (phen)CuR F, which react with aryl iodides and aryl boronates to form the corresponding benzotrifluorides. Herein the perfluoroalkylation of a series of heteroaryl bromides with (phen)CuCF3 and (phen)CuCF 2CF3 is reported. The mild reaction conditions allow the process to tolerate many common functional groups. Perfluoroethylation with (phen)CuCF2CF3 occurs in somewhat higher yields than trifluoromethylation with (phen)CuCF3, creating a method to generate fluoroalkyl heteroarenes that are less accessible from trifluoroacetic acid derivatives.
IMDOLIZINE DERIVATIVES AS LIGANDS OF THE CRTH2 RECEPTOR
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Page/Page column 63, (2008/06/13)
Compounds of formula (I) are CRTH2 antagonists, useful in the treatment of, for example, asthma, chronic obstructive pulmonary disease, rhinitis, allergic airway syndrome, and allergic rhinobronchitis. Formula (I) wherein R1, R2. R3 and R4 each independently are hydrogen, C1-C6alkyl, fully or partially fluorinated C1-C6alkyl, halo, -S(O)nR10, -SO2N(R10)2, -N(R10)2, -C(O)N(R10)2, -NR10C(O)R9, -CO2R10, -C(O)R9, -NO2, -CN or -OR11; wherein each R9 is independently C1-C6alkyl, aryl, heteroaryl; R10 is independently hydrogen, C1-C6alkyl, aryl, or heteroaryl; R11 is hydrogen, C1-C6alkyl, fully or partially fluorinated C1-C6alkyl or a group -SO2R10 ; n is 0, 1 or 2; R5 is C1-C6alkyl, fully or partially fluorinated C1-C6alkyl, C1-C6alkenyl, C1-C6alkynyl, optionally substituted aryl, or optionally substituted heteroaryl; R6 is hydrogen, C1-C6alkyl or fully or partially fluorinated C1-C6alkyl ; R7 and R8 are independently hydrogen or C1-C6alkyl, or R7 and R8 together with the atom to which they are attached form a cycloalkyl group; and X is -CHR6-, -S(O)n-, -C(O)-, -NR6SO2- or -SO2NR6- wherein n is 0, 1 or 2.
Reactions of Trifluoromethyl Bromide and Related Halides: Part 10. Perfluoroalkylation of Aromatic Compounds induced by Sulphur Dioxide Radical Anion Precursors
Tordeux, Marc,Langlois, Bernard,Wakselman, Claude
, p. 2293 - 2299 (2007/10/02)
Perfluoroalkylation of electron-rich aromatic compounds with trifluoromethyl bromide, or long-chain perfluoroalkyl iodides, was performed in the presence of sodium dithionite or zinc-sulphur dioxide.This alkylation occurred at the ortho and para positions relative to the amino or hydroxy substitutent.Pyrroles were perfluoroalkylated regioselectively at the 2-position.This alkylation was interpreted as a radical aromatic substitution; the formation of the perfluoroalkyl radical can be induced by a single-electron transfer from sulphur dioxide radical anion to the perfluoroalkyl halide.
Process for perfluoroalkylation of aromatic derivatives
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, (2008/06/13)
A process for the perfluoroalkylation of aromatic derivatives. In a first stage, an aromatic derivative, sulfur dioxide and a metal selected from the group consisting of zinc, aluminum, manganese, cadmium, magnesium, tin, iron, nickel and cobalt, are brought into contact in a solvent, preferably a polar aprotic solvent. In a second stage, a perfluoroalkyl bromide or iodide is added to react with the aromatic derivative.
