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Baran Group Meeting Changxia Yuan 4/5/2014 Commercial available peroxides* Inorganic peroxides Na2O2 CaO2 Li2O2 BaO2 Ni2O3 NiO2 xH2O H2O2(30%) ZnO2 NaBO3 4H2O MgO2 TbO2 SrO2 Na2CO3 1.5H2O sodium calcium lithium barium nickel nickel(II) hydrogen zinc sodium magnesium terbium Stronium sodium peroxide peroxide peroxide peroxide peroxide peroxide peroxide peroxide perborate peroxide peroxide peroxide percarbonate $ 109/100g $ 27/100g $ 32 /50g $ 146/500g $ 106/5g hydrate $ 350/4L $ 75/1kg tetrahydrate complex $ 30/1g $ 38/100g $ 91/ 2.5kg $ 40/ 1g $94/1kg $ 40/250g + (NH4)2S2O8 Na2S2O8 K2S2O8 2K2SO5 KHSO4 K2SO4 5[Bu4N ] SO5] HSO4] SO4] ammonium sodium potassium Oxone® OXONE® persulfate persulfate persulfate monopersulfate tetrabutylammonium salt $ 39/ 100g $ 87/ 2.5kg $ 70/ 500g compound $ 156/ 25g $ 60/ 1kg Organic peroxides-1 O CO3H O HOO tBu O O OO O CH2(CH2)9CH3 O H3C(H2C)9H2C O O tBu tBuOOH urea H2O2 BzOOBz OOH O Cl O tert-Butyl Urea Benzoyl mCPBA Cyclobutane 2-Butanone tert-Butyl Lauoyl hydroperoxide hydrogen peroxide $ 81/100g maloyl peroxide peroxide peroxide solution (5-6 M) peroxide $ 92/500g peroxide $ 129/500mL $ 134/1L $ 81/100g $ 47/25mL $ 88/ 250g $ 100/1g Cl O O Cl O Me Me O Me Me Me Me O O O O Ph O O O O OO O Me O Me O Ph O O tBu Cl Ph Me Me Me O Me 2,4-Dichlorobenzoyl Cl tert-Butyl tert-Butyl peracetate solution, Dicumyl tert-Butylperoxy 1,1-Bis(tert-amylperoxy)cyclohexane peroxide, 50% in DBP peroxybenzoate 50% in mineral spirits peroxide 2-ethylhexyl solution, 80% in mineral spirits $ 59/100g $ 86/500mL $ 77/500mL $ 123/500g carbonate $ 74/500g Me $ 77/500mL Me Et O OtBu O O OtBu O Me O O O O OtBu O tBu O O O O O O O OtBu O O O OH Et Me O O O Me Me Me Et O O Me tert-Butyl 1,3-Bis(2-tert-butylperoxyisopropyl) 1,1-Bis(tert-butylperoxy)-3,3,5- 3,6,9-Triethyl- 2,4-Pentanedione 2,2-Di(tert-butylperoxy) monoperoxymaleate benzene trimethylcyclohexane 3,6,9-trimethyl-1,4,7-triperoxonane peroxide solution butane $ 75/5g $ 150/250g $ 78/500mL $ 62/100g $ 45/500mL $ 86/500mL * Prices are based on Aldrich Inventory (price from other suppliers will not be noted); any resouce less than 10 mg will not be included Baran Group Meeting Changxia Yuan 4/5/2014 Hydrogen peroxide based oxidants: OTMS Me Me Me Me OH TBHP, MoO2(acac)2 Prep:H2O2 and Mo reagent mixing for the reaction;stable powder H2O2 (NH4)6Mo7O24 4H2O O Application: 1)[Mo] Among the best catalyst for the epoxidations benzene, CF CO H Hydrogen peroxide 3 2 since it is cheap and easy handling; 2)mono and di-subustituted 60 °C, 72 h ammonium heptamolybdate Me Me alkenes react very slowly 85% selectively on more hindered alcohol Tetrahedron. Lett. 1981, 2595. OH O O H O +[Mo] O Cl Me 2 2 Me Cl 1. TBHP, pyridine, CCl4,0°C TBA, K2CO3,THF,6d O 2. 96 °C 44% HO 90% HO Isr. J. Chem. 1984, 134. J. Am. Chem. Soc. 1975, 2281. O O O O O O Me O Cu(ClO4) 6H2O H TBHP Me OEt OMe Me H2O2 +[Mo] Me OEt O HO HO O NC CH3CN, 80 °C OOtBu tBuOO TBA, K2CO3,THF,4d H Ph Ph OEt OtBu 45% 66% HO 73% O H H 88% some noticeable examples without the base, epoxidation can occur J. Org. Chem. 2010, 5065-5071. J. Am. Chem. Soc. 1992, 7375. OtBu OtBu OtBu OtBu OtBu TBHP: TBHP, TMSN DHQ) Pyr O O Prep:70-90% aqueous solution or anhydrous solution in hydrocarbon solvents 3 2 N3 O N N3 O FeCl (0.1 eq) O (3 mol%) O 3 (Sharpless' Aldrich procedure to prepare anhydrous TBHP) 3 N3 N3 O Application: 1)oxidation of alkenes to diols; 2) oxidation of allylic or benzylic or H H R CH2Cl2,0°C R R=H R tBu propargylic positions with SeO2 and TBHP 3)epoxidation widely applied; 4) vicinal OOH diol can be cleaved by TBHP with MoO ; 5) alcohol can be oxidized by TBHP with R = H, alkyl, aryl moderate to high ee 2 32%, 93% ee 35%, 96% ee 90%, racemic tbutyl hydroperoxide Se or Cr compound; 6) sulfide can be oxidized to sulfoxide or sulfone; 7) 30-40% yield phosphanes can be oxidized to phphosphine oxide; 8)amine can be oxidized to N- Org. Lett. 2013, 3832. some noticeable examples oxide or imine; 9) Kharasch reaction; 10) peroxy acetal can be made from Antilla has chiral Bronsted Acid catalyzed peroxidation of imine on Angew. Chem. Int. Ed. 2010, 6589. aldehyde or ketone with TBHP; 12) alkyl halide can be converted to alkyl alcohol from Grignard reagent with TBHP. Me tBuOOH, AgOTf Me Br AgOTf Me OH OH Me Me HO O Me CH Cl ,0°C MeOH Me TBHP, VO(acac)2 Br Br 2 2 Me O O TBHP, SeO2 (5% mol) OOH benzene, 40 °C, 50 h 50% tBuOH OH O 78% Tetrahedron Lett. 1983, 543-546. 60% J. Chem. Soc. Perkin. Trans. 1. 1985, 267. Tetrahedron. Lett. 1976, 3157. mCPBA and its families: O H Prep:stable in 85% purity, 100% purity is possible, stored in polyethylene TBHP, CrO3 (5%) Cl O container in fridge O Application: 1) epoxidation of alkenes (electron-riched); 2) B-V reaction; CH2Cl2 O 3) Rubottum oxidation; 4) oxidation of sulfide to sulfoxide (tandemed with sole SeO gave oxidation on both sides 47% (9% sm) 2 meta-chloroperbenzoic acid Mislow-Evans rearrangement); 5) oxidation of selenides and phosphanes and phosphites; Tetrahedron. Lett. 1983, 2321. Baran Group Meeting Changxia Yuan 4/5/2014 mCPBA, EtOAc Persulfate based peroxide reagents: CH2Cl2,Na2CO3 (aq.) OH Application: 1) oxidizing primary and secondary alcohols to aldehyde w/o I CO2Me K2S2O8/(NH4)2S2O8 5 -20 °C, 1 hour CO2Me cat.(kinatically slow to acid; 2) oxidizing ether to aldehyde oxidizing aldehyde or ketones to benzoic acid with metal catalysts; 4)oxidizing aliphatic 65 - 67% potassium/ammonium peroxydisulfate amines to aldimines or nitriles with Cu(II)/Ni(II) as catalyst; 5)oxidizing J. Am. Chem. Soc. 1983, 2908. carboxylic acid to peracid under phase transfer condition; Elbs oxidation: O H OH Cl O Application: 1) oxidation of alcohol at room MeO O 1. K S O MeO O O + Me Me HCl temp for high yield; 2) epoxy ketone can be 2 2 8 N prepared in one step from allylic alcohol; 3) Me H Me 2. NaOH forced conditions lead to lactone or ester meta-chloroperbenzoic acid-2,2,6,6-tetramethylpiperidine from alcohol 40% hydrochloride OH O OH O O Me flavanol based structure through p-hydroxysulfate ester salts O Me H Me 1. mCPBA, TMPHCl Me H Chem. Rev. 1951, 49, 91. 2. hydrazine HO Boyland-Sims oxidation: HO Me Me Me Me Me Me Me Me N 68% N N - N SO3 J. Org. Chem. 1961, 3615. (H4N)O3S OOSO3(NH4) O OSO3K + KOH NO 2 Characterization:Stable at ambient temperature as white crystal; OSO3K Application: epoxidation of alkenes; B-V reaction o/p = 2/1, 22% O J. Org. Chem. 1992, 2266. H O C-H oxidation: O p-Nitrobenzoic peroxide Me OH K2S2O8,NaOAc,Cu(II) PNPBA, CHCl3 MeCN-HOAc, 80 °C reflux, 23 h 80% 69% Angew. Chemie. Engl. 1979, 407. J. Org. Chem. 1986, 3693. Me CO Me O O 2 K2S2O8,Fe(II) O H Me O O NaOAc-HOAc Me Ph O reflux OOH 81% Oxidation of alkenes: Tetrahedron. 1980, 3559. O CO3H Perbenzoic acid NH tButyl 4-benzoylperbenzoate p-Methoxyl NH 2 carbonylperbenzoic acid K S O N 2 2 8 N H SO /HOAc OH 80 °C OH epoxidation/B-V Prep: from corresponding benzoic acid N N 2 4 O Prep: from ester aldehyde which K2S2O8 + reaction/oxidation with tButyl hydrogperoxide. H2O, 80 °C was irradiated with 2 kW high EtOH, H2O HOSO of amine or sulfide N N 2 OH Application: low-temperature initiation pressure Mercury light with O ,as N 91% N 60% extremely like mCPBA (360 nm, compared to reflux of AIBN) of 2 R R Caro's acid stable as mCPBA; adenosine Peroxymonosulfuric acid radical reaction; Utilization : very similar as mCPBA Chem. Pharm. Bull. 1992, 1656. J. Org. Chem. 1960, 1901. Baran Group Meeting Changxia Yuan 4/5/2014 NO Oxidation of alcohols: 2 O O O O O O (ArSO3)2 (NH ) S O , Cu(II) S O OH 4 2 2 8 X X O O S AcOH, 100 °C O O X=OR,NR2 around 60% ONs O N 96% 2 p-Nitrobenzenesulfonyl peroxide J. Org. Chem. 1990, 1267. J. Org. Chem. 1983, 4914. J. Org. Chem. 1991, 1014. OH OH Application: Pseudohalogen reagent whose reactivity is comparable to that of chlorine; Na2S2O8 -hydroxy ketone can be made from enol derivatives (OTMS, OAc, NR2) CN O H2O, 60 °C CN CO H 40% 3 Preparation: o-sulfobenzoic anhydride and 30% H2O2 in acetone, stable in Bulll. Acad. Sci. USSR, Div. Chem. Sci. 1984, 2099. acetone; SO H Utilization: epoxidation and hydroxylation have been reported; sometimes the B-V C-H oxidation: 3 reaction gave better result compared to peracetic acid-Boron Etherate O o-Sulfoperbenzoic acid CO2H Na2S2O8 O Ag(I), Cu(II), O Preparation:insuwithKO2 and sulfonyl chloride Me MeCN, 80 °C O Application: epoxidation of alkenes (basic condition epoxidation); 56% S oxidation of benzylic position (few case); oxidative desulfurization of Tetrahedron. Lett. 1985, 2525. O OK thiocarbonyl compounds (sulfuryl urea to urea) H NO2 2KHSO KHSO K SO experiments suggested a radical 5 4 2 4 Potassium oxone o-Nitrobenzeneperoxysulfonate under dimethyldioxirine item K2S2O8 Me 2+ R N HOAc/KOAc H2O, 100 °C R R OH R=H O [Ag] N N 2- 86% S2O8 R=H Ag isomer distribution N N subs.
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  • Newly Observed Peroxides and the Water Effect on the Formation And

    Newly Observed Peroxides and the Water Effect on the Formation And

    EGU Journal Logos (RGB) Open Access Open Access Open Access Advances in Annales Nonlinear Processes Geosciences Geophysicae in Geophysics Open Access Open Access Natural Hazards Natural Hazards and Earth System and Earth System Sciences Sciences Discussions Open Access Open Access Atmos. Chem. Phys., 13, 5671–5683, 2013 Atmospheric Atmospheric www.atmos-chem-phys.net/13/5671/2013/ doi:10.5194/acp-13-5671-2013 Chemistry Chemistry © Author(s) 2013. CC Attribution 3.0 License. and Physics and Physics Discussions Open Access Open Access Atmospheric Atmospheric Measurement Measurement Techniques Techniques Discussions Open Access Newly observed peroxides and the water effect on the formation and Open Access removal of hydroxyalkyl hydroperoxides in the ozonolysis of Biogeosciences Biogeosciences isoprene Discussions D. Huang, Z. M. Chen, Y. Zhao, and H. Liang Open Access Open Access State Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Climate Engineering, Peking University, Beijing 100871, China Climate of the Past of the Past Correspondence to: Z. M. Chen ([email protected]) Discussions Received: 5 January 2013 – Published in Atmos. Chem. Phys. Discuss.: 25 February 2013 Open Access Open Access Revised: 4 May 2013 – Accepted: 15 May 2013 – Published: 12 June 2013 Earth System Earth System Dynamics Dynamics Abstract. The ozonolysis of alkenes is considered to be an lows them to become involved in atmospheric chemical pro- Discussions important source of atmospheric peroxides, which serve as cesses, e.g., SOA formation and radical recycling. oxidants, reservoirs of HOx radicals, and components of sec- Open Access ondary organic aerosols (SOAs). Recent laboratory investi- Geoscientific Geoscientific Open Access gations of this reaction identified hydrogen peroxide (H2O2) Instrumentation Instrumentation and hydroxymethyl hydroperoxide (HMHP) in ozonolysis 1 Introduction Methods and Methods and of isoprene.
  • The Mechanism of the Baeyer–Villiger Rearrangement: Quantum Chemistry and TST Study Supported by Experimental Kinetic Data†

    The Mechanism of the Baeyer–Villiger Rearrangement: Quantum Chemistry and TST Study Supported by Experimental Kinetic Data†

    PAPER www.rsc.org/obc | Organic & Biomolecular Chemistry The mechanism of the Baeyer–Villiger rearrangement: quantum chemistry and TST study supported by experimental kinetic data† J. Raul Alvarez-Idaboy,*a Lino Reyesa and Nelaine Mora-Diezb Received 15th August 2007, Accepted 19th September 2007 First published as an Advance Article on the web 2nd October 2007 DOI: 10.1039/b712608e The mechanism of the Baeyer–Villiger rearrangement is modelled for the reaction of propanone with trifluoroperacetic acid, catalyzed by trifluoroacetic acid in dichloromethane, using three DFT methods (B3LYP, BH&HLYP and MPWB1K) and MP2. These results are refined and used to calculate the overall reaction rate coefficient using conventional Transition State Theory. The excellent agreement between the calculated (1.00 × 10−3 L mol−1 s−1) and the experimental (1.8 × 10−3 L mol−1 s−1)rate coefficients at the MPWB1K level strongly supports the mechanism recently proposed by our group. This DFT method is then used to study the mechanism of a larger system: cyclohexanone + trifluoroperacetic acid, for which a very good agreement between the calculated and the experimental rate coefficients is also found (1.37 and 0.32 L mol−1 s−1, respectively). The modelled mechanism is not ionic but neutral, and consists of two concerted steps. The first one is strongly catalyzed while the second one, the migration step, seems not to be catalyzed for the systems under study. The results of this work could be of interest for understanding other reactions in non-polar solvents for which ionic mechanisms have been assumed.