Hydrogen Bonding to Hexafluoroisopropanol Controls the Oxidative Strength of Hypervalent Iodine Reagents.

Hexafluoroisopropan-2-ol (HFIP) has been found to be an unusually beneficial solvent for undertaking hypervalent iodine-initiated [2+2] cycloaddition of styrenes. For the initiator phenyliodine(III) diacetate (PIDA), voltammetric data demonstrate that the enhanced reactivity in HFIP is due to its greater oxidizing abilities in this fluorinated solvent such that in HFIP the reactivity of PIDA is comparable if not superior to its fluorinated analog phenyliodine(III) bis(trifluoroacetate). These results contrast with the often reported view that the role of the fluoroalcohol is to stabilize a radical cation formed by single electron transfer. Moreover, combined NMR and HRMS results reveal the formation of a strong H-bonded adduct between the solvent and oxidizing reagent which is the physical origin of the observed altered synthetic reactivity.

[1]  Johnathan N. Brantley,et al.  Isolation and Reactivity of Trifluoromethyl Iodonium Salts , 2016, ACS central science.

[2]  Ignacio Colomer,et al.  Catalytic Hypervalent Iodine Promoters Lead to Styrene Dimerization and the Formation of Tri- and Tetrasubstituted Cyclobutanes. , 2016, Angewandte Chemie.

[3]  Durga Prasad Hari,et al.  Cyclic Hypervalent Iodine Reagents for Atom-Transfer Reactions: Beyond Trifluoromethylation. , 2016, Angewandte Chemie.

[4]  K. Morimoto,et al.  Organo-Iodine(III)-Catalyzed Oxidative Phenol-Arene and Phenol-Phenol Cross-Coupling Reaction. , 2016, Angewandte Chemie.

[5]  Akira Yoshimura,et al.  Advances in Synthetic Applications of Hypervalent Iodine Compounds. , 2016, Chemical reviews.

[6]  M. K. Brown,et al.  Cyclobutane and cyclobutene synthesis: catalytic enantioselective [2+2] cycloadditions. , 2015, Angewandte Chemie.

[7]  P. Chirik,et al.  Iron-catalyzed intermolecular [2+2] cycloadditions of unactivated alkenes , 2015, Science.

[8]  Andrew J Boydston,et al.  Metal-Free Preparation of Linear and Cross-Linked Polydicyclopentadiene. , 2015, Journal of the American Chemical Society.

[9]  Njamkou N. Noucti,et al.  Stereoselective nickel-catalyzed [2+2] cycloadditions of ene-allenes. , 2015, Angewandte Chemie.

[10]  M. Stewart,et al.  Electron-transfer catalyzed cycloaddition reactions of unactivated cyclic olefins in weakly coordinating anion electrolyte , 2015 .

[11]  Andrew J Boydston,et al.  Metal-free ring-opening metathesis polymerization. , 2015, Journal of the American Chemical Society.

[12]  V. Dembitsky.  Naturally occurring bioactive Cyclobutane-containing (CBC) alkaloids in fungi, fungal endophytes, and plants. , 2014, Phytomedicine : international journal of phytotherapy and phytopharmacology.

[13]  P. Margaretha.  Retrospective View on Recent Developments in Cyclobutane Synthesis via [2+2] Photocycloaddition of Unsaturated Ketones to Acyclic Dienes , 2014 .

[14]  K. Morimoto,et al.  Organocatalytic C–H/C–H' cross-biaryl coupling: C-selective arylation of sulfonanilides with aromatic hydrocarbons. , 2013, Journal of the American Chemical Society.

[15]  David A. Nicewicz,et al.  Synthesis of cyclobutane lignans via an organic single electron oxidant-electron relay system. , 2013, Chemical science.

[16]  M. A. Ischay,et al.  Crossed Intermolecular [2+2] Cycloaddition of Styrenes by Visible Light Photocatalysis. , 2012, Chemical science.

[17]  A. Togni,et al.  Reactivity of an electrophilic hypervalent iodine trifluoromethylation reagent with hydrogen phosphates—A mechanistic study , 2012 .

[18]  R. Kötz,et al.  Novel electrolytes for electrochemical double layer capacitors based on 1,1,1,3,3,3-hexafluoropropan-2-ol , 2012 .

[19]  Rebecca L. Davis,et al.  Asymmetric organocatalytic formal [2 + 2]-cycloadditions via bifunctional H-bond directing dienamine catalysis. , 2012, Journal of the American Chemical Society.

[20]  J. Mascareñas,et al.  Ruthenium-catalyzed (2 + 2) intramolecular cycloaddition of allenenes. , 2011, Journal of the American Chemical Society.

[21]  T. Dohi,et al.  Fluoroalcohols: versatile solvents in hypervalent iodine chemistry and syntheses of diaryliodonium(III) salts , 2010 .

[22]  M. A. Ischay,et al.  [2+2] cycloadditions by oxidative visible light photocatalysis. , 2010, Journal of the American Chemical Society.

[23]  K. Morimoto,et al.  Unusual ipso substitution of diaryliodonium bromides initiated by a single-electron-transfer oxidizing process. , 2010, Angewandte Chemie.

[24]  J. Qu,et al.  Friedel-Crafts alkylation of arenes with epoxides promoted by fluorinated alcohols or water. , 2010, Chemical communications.

[25]  Hajime Ito,et al.  Stereospecific synthesis of cyclobutylboronates through copper(I)-catalyzed reaction of homoallylic sulfonates and a diboron derivative. , 2010, Journal of the American Chemical Society.

[26]  K. Morimoto,et al.  Hypervalent iodine(III): selective and efficient single-electron-transfer (SET) oxidizing agent , 2009 .

[27]  J. Welch,et al.  Acid-mediated formation of trifluoromethyl sulfonates from sulfonic acids and a hypervalent iodine trifluoromethylating agent. , 2009, Chemical communications.

[28]  A. Togni,et al.  Zinc-mediated formation of trifluoromethyl ethers from alcohols and hypervalent iodine trifluoromethylation reagents. , 2009, Angewandte Chemie.

[29]  M. Stewart,et al.  Cycloaddition reactions of unactivated olefins catalyzed by an organorhenium electron-transfer mediator. , 2009, Journal of the American Chemical Society.

[30]  K. Morimoto,et al.  Metal-free oxidative cross-coupling of unfunctionalized aromatic compounds. , 2009, Journal of the American Chemical Society.

[31]  M. Ratnikov,et al.  Lewis acid catalyst free electrophilic alkylation of silicon-capped pi donors in 1,1,1,3,3,3-hexafluoro-2-propanol. , 2008, Angewandte Chemie.

[32]  N. Lopes,et al.  Application of high-resolution electrospray mass spectrometry for the elucidation of the disproportionation reaction of iodobenzene diacetate , 2008 .

[33]  V. Poroikov,et al.  Cyclobutane-Containing Alkaloids: Origin, Synthesis, and Biological Activities , 2008, The open medicinal chemistry journal.

[34]  Abigail G Doyle,et al.  Small-molecule H-bond donors in asymmetric catalysis. , 2007, Chemical reviews.

[35]  I. Raheem,et al.  Enantioselective Pictet-Spengler-type cyclizations of hydroxylactams: H-bond donor catalysis by anion binding. , 2007, Journal of the American Chemical Society.

[36]  Diane K. Smith,et al.  Voltammetry of quinones in unbuffered aqueous solution: reassessing the roles of proton transfer and hydrogen bonding in the aqueous electrochemistry of quinones. , 2007, Journal of the American Chemical Society.

[37]  A. Börner,et al.  Fluorinated Alcohols as Solvents, Cosolvents and Additives in Homogeneous Catalysis , 2007 .

[38]  F. Toste,et al.  Gold(I)-catalyzed [2 + 2]-cycloaddition of allenenes. , 2007, Journal of the American Chemical Society.

[39]  Valery M. Dembitsky,et al.  Bioactive cyclobutane-containing alkaloids , 2007, Journal of Natural Medicines.

[40]  A. Berkessel,et al.  Dramatic acceleration of olefin epoxidation in fluorinated alcohols: activation of hydrogen peroxide by multiple h-bond networks. , 2006, Journal of the American Chemical Society.

[41]  J. Neudörfl,et al.  Unveiling the "booster effect" of fluorinated alcohol solvents: aggregation-induced conformational changes and cooperatively enhanced H-bonding. , 2006, Journal of the American Chemical Society.

[42]  K. Chiba,et al.  Electrochemical enol ether/olefin cross-metathesis in a lithium perchlorate/nitromethane electrolyte solution. , 2006, Angewandte Chemie.

[43]  A. Studer,et al.  Stereoselective cyclization reactions of IBX-generated alkoxyamidyl radicals. , 2005, The Journal of organic chemistry.

[44]  Y. Kita,et al.  A novel and direct synthesis of chroman derivatives using a hypervalent iodine(III) reagent , 2004 .

[45]  J. D. Figueroa-Villar,et al.  Formation of p-cresol:piperazine complex in solution monitored by spin-lattice relaxation times and pulsed field gradient NMR diffusion measurements. , 2003, Journal of magnetic resonance.

[46]  K. Nicolaou,et al.  Iodine(V) reagents in organic synthesis. Part 3. New routes to heterocyclic compounds via o-iodoxybenzoic acid-mediated cyclizations: generality, scope, and mechanism. , 2002, Journal of the American Chemical Society.

[47]  T. Steiner.  The hydrogen bond in the solid state. , 2002, Angewandte Chemie.

[48]  S. Berger,et al.  DOSY studies of hydrogen bond association: tetramethylsilane as a reference compound for diffusion studies , 2001 .

[49]  K. Chiba,et al.  Electrocatalytic intermolecular olefin cross-coupling by anodically induced formal [2+2] cycloaddition between enol ethers and alkenes. , 2001, Journal of the American Chemical Society.

[50]  K. Nicolaou,et al.  Mechanistic Studies of Periodinane-Mediated Reactions of Anilides and Related Systems. , 2001, Angewandte Chemie.

[51]  S. Berger,et al.  The qualitative probing of hydrogen bond strength by diffusion-ordered NMR spectroscopy , 2000 .

[52]  F. Radner,et al.  Making radical cations live longer , 1997 .

[53]  H. Sakurai,et al.  Hypervalent Iodine-Induced Nucleophilic Substitution of para-Substituted Phenol Ethers. Generation of Cation Radicals as Reactive Intermediates , 1994 .

[54]  N. L. Bauld,et al.  CATION RADICAL CATALYZED OLEFIN CYCLODIMERIZATION , 1983 .

[55]  K. Purcell,et al.  Spectroscopic studies of hydrogen bonding: Hexafluoroisopropanol☆ , 1969 .

[56]  T. Wirth.  Hypervalent Iodine Chemistry , 2003 .

[57]  A. Bard,et al.  KINETICS AND MECHANISM OF THE ANODIC DIMERIZATION OF TRANS-ANETHOLE STUDIED BY CYCLIC VOLTAMMETRY AND SCANNING ELECTROCHEMICAL MICROSCOPY , 1999 .

[58]  F. Radner,et al.  1,1,1,3,3,3-HEXAFLUOROPROPAN-2-OL (HFP) AS A SOLVENT FOR ELECTROCHEMISTRY , 1998 .

[59]  Y. Kita,et al.  A novel oxidative azidation of aromatic compounds with hypervalent iodine reagent, phenyliodine(III) bis(trifluoroacetate) (PIFA) and trimethylsilyl azide , 1991 .

[60]  B. Jursic,et al.  1H nmr study of hydrogen bonding of fluorinated alcohols with ethers , 1985 .