887144-97-0Relevant articles and documents
Supramolecular Aggregation of Perfluoroorganyl Iodane Reagents in the Solid State and in Solution
Liebing, Phil,Pietrasiak, Ewa,Otth, Elisabeth,Kalim, Jorna,Bornemann, Dustin,Togni, Antonio
, p. 3771 - 3781 (2018/07/31)
The crystal structures of different perfluoroorganyl iodanes are described, including those of four new benziodoxole derivatives with RF = n-C3F7, n-C4F9, n-C8F17, and C6F5. In all of the compounds, the iodine atom shows significant Lewis acidity, and the fourth coordination site is readily filled by secondary bonding interactions to produce square-planar coordination. Although this geometry is a good model for benziodoxoles, benziodoxolone derivatives tend to aggregate further through additional weak I···O or I···aryl contacts. The different interactions lead to the formation of various assemblies with different dimensions in the solid state. The protonation of the reagents results in the formation of entirely different supramolecular structures, which are supported by hydrogen bonding. The structural features of the reagents in the solid state reflect well their behavior in solution, and the I–C(RF) bond is influenced by the coordination of Lewis basic solvents to the iodine atom and by hydrogen bonding with protic solvents. These solvent effects are more pronounced for reagents containing the trifluoromethyl fragment than for derivatives with longer RF chains.
Borazine-CF3? Adducts for Rapid, Room Temperature, and Broad Scope Trifluoromethylation
Geri, Jacob B.,Wade Wolfe, Michael M.,Szymczak, Nathaniel K.
supporting information, p. 1381 - 1385 (2018/01/15)
A fluoroform-derived borazine CF3? transfer reagent is used to effect rapid nucleophilic reactions in the absence of additives, within minutes at 25 °C. Inorganic electrophiles spanning seven groups of the periodic table can be trifluoromethylated in high yield, including transition metals used for catalytic trifluoromethylation. Organic electrophiles included (hetero)arenes, enabling C?H and C?X trifluoromethylation reactions. Mechanistic analysis supports a dissociative mechanism for CF3? transfer, and cation modification afforded a reagent with enhanced stability.
Recyclable Trifluoromethylation Reagents from Fluoroform
Geri, Jacob B.,Szymczak, Nathaniel K.
supporting information, p. 9811 - 9814 (2017/08/03)
We present a strategy to rationally prepare CF3- transfer reagents at ambient temperature from HCF3. We demonstrate that a highly reactive CF3- adduct can be synthesized from alkali metal hydride, HCF3, and borazine Lewis acids in quantitative yield at room temperature. These nucleophilic reagents transfer CF3- to substrates without additional chemical activation, and after CF3 transfer, the free borazine is quantitatively regenerated. These features enable syntheses of popular nucleophilic, radical, and electrophilic trifluoromethylation reagents with complete recycling of the borazine Lewis acid.
COMPLEXES FOR NUCLEOPHILIC, RADICAL, AND ELECTROPHILIC POLYFLUOROALKYLATION
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Paragraph 00163, (2018/04/11)
Disclosed herein are borazine complexes and use of the same in perfluoroalkylation reactions.
One-pot synthesis of hypervalent iodine reagents for electrophilic trifluoromethylation
Matousek, Vaclav,Pietrasiak, Ewa,Schwenk, Rino,Togni, Antonio
, p. 6763 - 6768 (2013/07/26)
Simplified syntheses suited for large scale preparations of the two hypervalent iodine reagents 1 and 2 for electrophilic trifluoromethylation are reported. In both cases, the stoichiometric oxidants sodium metaperiodate and tert-butyl hypochlorite have been replaced by trichloroisocyanuric acid. Reagent 1 is accessible in a one-pot procedure from 2-iodobenzoic acid in 72% yield. Reagent 2 was prepared via fluoroiodane 11 in a considerably shorter reaction time and with no need of an accurate temperature control.
Connecting binuclear Pd(III) and mononuclear Pd(IV) chemistry by Pd-Pd bond cleavage
Powers, David C.,Lee, Eunsung,Ariafard, Alireza,Sanford, Melanie S.,Yates, Brian F.,Canty, Allan J.,Ritter, Tobias
supporting information; experimental part, p. 12002 - 12009 (2012/09/08)
Oxidation of binuclear Pd(II) complexes with PhICl2 or PhI(OAc)2 has previously been shown to afford binuclear Pd(III) complexes featuring a Pd-Pd bond. In contrast, oxidation of binuclear Pd(II) complexes with electrophilic trifluoromethylating ("CF3 +") reagents has been reported to afford mononuclear Pd(IV) complexes. Herein, we report experimental and computational studies of the oxidation of a binuclear Pd(II) complex with "CF3 +" reagents. These studies suggest that a mononuclear Pd(IV) complex is generated by an oxidation-fragmentation sequence proceeding via fragmentation of an initially formed, formally binuclear Pd(III), intermediate. The observation that binuclear Pd(III) and mononuclear Pd(IV) complexes are accessible in the same reactions offers an opportunity for understanding the role of nuclearity in both oxidation and subsequent C-X bond-forming reactions.
New hypervalent iodine reagents for electrophilic trifluoromethylation and their precursors: Synthesis, structure, and reactivity
Niedermann, Katrin,Welch, Jan M.,Koller, Raffael,Cvengro, Ján,Santschi, Nico,Battaglia, Philip,Togni, Antonio
scheme or table, p. 5753 - 5761 (2010/09/18)
Several new five- and a six-membered heterocyclic monochloroiodanes, including two cationic species, were synthesized. Three of which were used for the preparation of corresponding trifluoromethylation reagents. These compounds were characterized by X-ray crystallography for a comparative structural study. A reactivity study on the trifluoromethylation of para-toluenesulfonic acid has been conducted in order to compare initial rates. Compounds having a longer I-O bond display a higher reactivity.
Recent advances in electrophilic CF3-transfer using hypervalent iodine(III) reagents
Kieltsch, Iris,Eisenberger, Patrick,Stanek, Kyrill,Togni, Antonio
scheme or table, p. 260 - 263 (2009/04/07)
The development of new methodologies for an efficient introduction of CF3 groups into complex molecules constitutes one of the most challenging tasks of modern organic chemistry. Recently, we reported the access to a new class of electrophilic CF3-transfer reagents based on hypervalent iodine. The versatile application of these reagents to C-centred nucleophiles, such as β-keto esters, silyl enol ethers and α-nitro esters, as well as to thiols and primary and secondary phosphines is described. Experiments with phenols afforded corresponding trifluomethylethers in very low yields. Schweizerische Chemische Gesellschaft.
Mild electrophilic trifluoromethylation of carbon- and sulfur-centered nucleophiles by a hypervalent iodine(III)-CF3 reagent
Kieltsch, Iris,Eisenberger, Patrick,Togni, Antonio
, p. 754 - 757 (2007/10/03)
Inexpensive, recyclable, and activable: these are the features of a new mild electrophilic trifluoromethylation reagent that can be used to transfer a CF3 group to C-centered nucleophiles, such as β-keto esters and α-nitro esters, and to S-centered nucleophiles (see scheme). (Chemical Equation Presented).
