- NEW METHOD FOR THE PREPARATION OF t-BUTYLDIMETHYLSILYL TRIFLATE
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t-Butyldimethylsilyl triflate is easily prepared from the reaction of triflic acid with isopropenyltrimethylsilane.
- Hudrlik, Paul F.,Kulkarni, Ashok K.
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- ELECTROPHILE-INITIATED SELECTIVE RING TRANSFORMATIONS OF CYCLOPROPYL KETONES
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Electrophile-mediated cyclopropane cleavage in tricyclo2,8>octan-3-one (1a) is increasingly directed towards the maximum bond overlap site in the following order of reagents: acetyl methanesulfonate, +Br(1-) or I(1-); t-butyl-dimethylsilyl iodide; t-butyldimethylsilyl trifluoroacetate; trimethylsilyl trifluoroacetate.The latter reagent gives rise to one single regioisomer (->6a).Routine yields of isolated products lie between 78 and 87percent.Increasing regioselectivity is governed by increasing electrophilic power and lowered nucleophilic strength of the reagents.Independent of these two factors, a C(4)-exo substituent in 1 directs the opening modes undirectionally (->2b, 6b).Irrespective of the substitution pattern at C(4) (1a-d), the cyclopropane moiety rearranges smoothly to olefinic ketones (8a-d) when the polymer-supported triflate analog Nafion-TMS is used in toluene at 80 deg C.The reaction proceeds via intramolecular proton (deuterion) abstraction by the transient electron-rich enoxy double bond.This is the first fully proved case of such an intramolecular process.Aro-semibullvalenes (18,22) similarly rearrange to aro-semibarrelenes (e.g. 21, 23) in the presence of Nafion-TMS.The latter rearrangement also takes place at room temperature when 18 or 22 are treated with commercial tetramethylsilane (TMS) and a catalytic amount of trifluoroacetic acid.An unknown impurity in the TMS reacts with the acid to form a powerful electrophilic composition.A cheap and convenient in situ preparation of TMS-triflate is described by mixing trifluoromethanesulfonic acid and TMS at room temperature.
- Demuth, Martin,Mikhail, Gamal
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- REAGENTS AND SYNTHETIC METHODS 55. NEW METHODS FOR THE PREPARATION OF t-BUTYLDIMETHYLSILYL TRIFLATE AND TRIMETHYLSILYL TRIFLATE.
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An expeditious synthesis of t-butyldimethylsilyl triflate is described from triflic acid and t-butyldimethylsilane.Reaction between trichloromethyltrimethylsilane and triflic acid is also reported.
- Aizpurua, Jesus M.,Palomo, Claudio
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- Further reactions of chlorine(I) and bromine(I) trifluoromethanesulfonate and bromine(I)fluorosulfate
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Substitutive electrophilic dehalogenation reactions of CF3SO2OX (X=Cl,Br) are reported with some covalent inorganic chlorides. These reactions result in the formation of XX′(X,X′Cl,Br) and several new trifluoromethanesulfonate derivatives in excellent yields. Chlorine(I) trifluoromethanesulfonate also oxidatively adds to unsaturated inorganic substrates such as CO, SO2 and SF4 forming new compounds. The reactivity of CF3SO2OCl is rather similar to that of FSO2OBr and some comparisons between the two are given.
- Johri, Kamalesh K.,Katsuhara, Yutaka,DesMarteau, Darryl D.
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- Synthesis method of trimethylsilyl trifluoromethanesulfonate
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The invention relates to a synthesis method of trimethylsilyl trifluoromethanesulfonate. The target product trimethylsilyl trifluoromethanesulfonate is synthesized by taking trifluoromethanesulfonic acid and trimethylchlorosilane as main raw materials and n-heptane as a solvent through a one-step method. The method has the advantages of simple and easily available raw materials, simple and convenient operation, mild synthesis conditions, and good social and economic benefits.
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Paragraph 0018-0023
(2021/04/29)
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- Divergent Synthesis of Vinyl-, Benzyl-, and Borylsilanes: Aryl to Alkyl 1,5-Palladium Migration/Coupling Sequences
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Organosilicon compounds have been extensively utilized both in industry and academia. Studies on the syntheses of diverse organosilanes is highly appealing. Through-space metal/hydrogen shifts allow functionalization of C?H bonds at a remote site, which are otherwise difficult to achieve. However, until now, an aryl to alkyl 1,5-palladium migration process seems to have not been presented. Reported herein is the remote olefination, arylation, and borylation of a methyl group on silicon to access diverse vinyl-, benzyl-, and borylsilanes, constituting a unique C(sp3)?H transformation based on a 1,5-palladium migration process.
- Han, Jie-Lian,Ju, Cheng-Wei,Qin, Ying,Zhao, Dongbing
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supporting information
p. 6555 - 6560
(2020/03/03)
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- A kind of triflic acid trimethyl Estersil method for the preparation of
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The invention relates to a preparation method of Trimethylsilyl trifluoromethanesulfonate, and belongs to the field of a fine chemical industry. The preparation method comprises the following specific steps: a compound of which the general formula is CF3SO2X reacts with hydroxytrimethylsilane, wherein X is Cl, F or OSO2CF3, and hydroxytrimethylsilane is used as a silicon alkylation reagent of the reaction; the reduced pressure distillation is carried out on a reaction mixture after the reaction is finished to collect Trimethylsilyl trifluoromethanesulfonate of which the mass content is higher than 99.0%, wherein the mole ratio of the CF3SO2X to the hydroxytrimethylsilane in the reaction is (1.00: 0.80) to (1.00: 1.60), the reaction time is 1 to 10 hours, the reduced pressure distillation is carried out on the reaction mixture after the reaction is finished, and the pressure is 0.005 to 0.030MPa.
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Paragraph 0113-0116
(2017/04/11)
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- Redox Reactions of a Stable Dialkylphosphinyl Radical
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A stable dialkylphosphinyl radical, 2,2,5,5-tatrakis(trimethylsilyl)-1-phosphacyclopentan-1-yl (RH2P?), showed both irreversible one-electron oxidation and reduction peaks at -0.24 and -2.29 V vs ferrocene/ferrocenium couple. One-electron reduction of RH2P? with KC8 in the presence of 18-crown-6 (18-c-6) or [2.2.2]cryptand (crypt-222) gave the corresponding phosphides [K(18-c-6)]+[RH2P]- and [K(crypt-222)]+[RH2P]-. Whereas [K(18-c-6)]+[RH2P]- exists as a contact ion pair, [K(crypt-222)]+[RH2P]- exists as a solvent-separated ion pair in the solid state. Reaction of RH2P? with AgOTf afforded an unexpected product, a silver(I) phosphaalkene complex. (Chemical Equation Presented).
- Hirakawa, Fumiya,Ichikawa, Hitomi,Ishida, Shintaro,Iwamoto, Takeaki
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supporting information
p. 2714 - 2716
(2015/06/30)
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- Versatile reagent Ph3As(OTf)2: One-pot synthesis of [P7(AsPh3)3][OTf]3 from PCl3
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Compound Ph3As(OTf)2 as a pentacoordinated AsV Lewis acid readily forms dicationic Lewis acid/base ad-ducts upon addition of various Lewis bases. It also represents a stronger chloride-abstracting agent than Me3SiOTf and facilitates the reductive coupling of PCl3 in the presence of AsPh3 to the unprecedented cation [P7(AsPh3)3]3+ as triflate salt. This crystallographically characterized nor-tricyclane-type cation represents a P7R3-derivative with the most electron-withdrawing substituents, resulting in a pronounced effect on the structural parameters of the P7 core.
- Donath, Maximilian,Bodensteiner, Michael,Weigand, Jan J.
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supporting information
p. 17306 - 17310
(2015/02/19)
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- Reaction of Carbodiimides with trifluoromethanesulfonic acid
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Carbodiimides RN=C=NR (R = i-Pr, c-C6H11, Ph) react with trifluoromethanesulfonic acid with successive formation of O-triflyl isoureas RNHC(OTf)=NR, the isomeric N-triflyl ureas RN(Tf)C(O)NHR, and symmetrically substituted ureas RNHC
- Tolstikova,Shainyan,Chipanina
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p. 1853 - 1858
(2014/01/06)
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- Reaction of 10,10-dimethyl-9-trimethylsiloxy-9,10-dihydrophenanthrene-9- carbonitrile with acids
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The behavior of 10,10-dimethyl-9-trimethylsiloxy-9,10-dihydrophenanthrene- 9-carbonitrile in trifluoromethanesulfonic acid and acid systems CF 3SO3H-CD2Cl2, HSO 3F-SO2ClF-CD2Cl2, and CF 3COOH-CD2Cl2 were studied by NMR spectroscopy. Principal reaction schemes were determined; the first step in these schemes is protonation of the initial compound at the oxygen or nitrogen atom.
- Bushmelev,Genaev,Sal'nikov,Shubin
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experimental part
p. 1057 - 1061
(2011/11/12)
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- Reaction of the Ruppert-Prakash reagent with perfluorosulfonic acids
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A new property of Me3SiCF3 to undergo C-F bond activation upon interaction with perfluorosulfonic acids is described. The reaction is catalyzed by titanium tetrachloride and affords difluoromethyl perfluorosulfonates in good yields.
- Levin, Vitalij V.,Dilman, Alexander D.,Belyakov, Pavel A.,Struchkova, Marina I.,Tartakovsky, Vladimir A.
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experimental part
p. 667 - 670
(2009/12/22)
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- Overall pseudocationic trifluoromethylation of dihydropyridines with triflic anhydride
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A triflic reaction: The role of triflic anhydride is not limited to the transfer of a triflyl group to the nitrogen atom during the interaction of pyridine with bis(trimethylsilyl) ketene acetals: it can also provide an electrophilic CF3 group able to transform the formed dihydropyridines substituted with trimethylsilyl ester groups into a-trifluoromethyllactones (see scheme). (Chemical Equation Presented)
- Rudler, Henri,Parlier, Andree,Sandoval-Chavez, Cesar,Herson, Patrick,Daran, Jean-Claude
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scheme or table
p. 6843 - 6846
(2009/04/06)
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- METHOD FOR PRODUCING GUANIDINIUM SALTS
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The invention relates to a two-stage method for producing guanidinium salts of formula (1), wherein the substituents R have the designation cited in patent claim 1, and A- is a sulfonate, an alkyl or aryl sulfate, a hydrogen sulfate, a imide, a methanide, a carboxylate, a phosphate, a phosphinate, a phosphonate, a borate, a thiocyanate, a perchlorate, a fluorosilicate or a nitrate. The invention also relates to intermediate compounds produced by said method.
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Page/Page column 35
(2008/06/13)
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- Catalyst for use in production of epoxide, method for producing the catalyst, and method for producing epoxide
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To provide an epoxide-production-use catalyst that is suitably used for producing an epoxide by partial oxidation of an unsaturated hydrocarbon, a catalyst in accordance with the present invention is obtained by fixing gold fine particles to a carrier containing an oxide containing at least one of titanium and zirconium, and has an acid quantity of not more than 0.1 mmol/g determined by the NH3-TPD method. Such a catalyst for epoxide producing use can be produced by, for instance, fixing gold fine particles to a carrier having an acid quantity of not more than 0.15 mmol/g. The catalyst for epoxide producing use arranged as above is preferably used as a catalyst in partial oxidation of an unsaturated hydrocarbon to produce a corresponding epoxide.
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- Tris(trimethylsilyl)sulfonium and Methylbis(trimethylsilyl)sulfonium Ions: Preparation, NMR Spectroscopy, and Theoretical Studies
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Tris(trimethylsilyl)sulfonium 1 and methylbis(trimethylsilyl)sulfonium 2 ions were prepared as long-lived species by reacting trimethylsilane and trityl tetrakis(pentafluorophenyl)borate (Ph3C+ TPFPB) in the presence of precursor sulfides and characterized by 1H, 13C, and 29Si NMR spectroscopy at -78°C. Attempted preparation of dimethyl(trimethylsilyl)sulfonium ion under similar conditions failed as a result of the formation of the more stabilized trimethylsulfonium ion. Structures, and 13C and 29Si NMR chemical shifts were calculated by density functional theory (DFT)IGLO methods. The calculated results agree well with the experimental data.
- Prakash, G. K. Surya,Bae, Chulsung,Wang, Qunjie,Rasul, Golam,Olah, George A.
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p. 7646 - 7649
(2007/10/03)
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- Polynucleoside chain having multiple ribonucleosides, the nucleosides coupled by guanidyl linkages
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The invention provides a cationic polynucleoside chain having multiple nucleosides, the nucleosides being coupled together by positively charged guanidyl linkages.
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- Mukaiyama Aldol Reactions Catalyzed by Zirconocene Bis(triflate) Complexes: Stereochemistry and Mechanisms for C-C Bond Formation
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The aldol condensations of α- and β-(benzyloxy) aldehydes with enol silanes, catalyzed by Cp2Zr(OTf)2THF or Cp2Zr(OTf)2, in a variety of solvents were studied. The simple diastereoselectivity of these reactions is modest and comparable to that observed using simple aldehydes of similar steric requirements. Studies have revealed that TMSOTf is directly produced on reaction with the zirconocene catalyst with the enol silane in nitroalkane solvent or is formed during catalysis in dichloromethane solution. Although TMSOTf is known to catalyze cross-aldol reactions under these conditions, the rate of this process is not always competitive with that observed using the zirconocene catalysts. In particular, sterically unhindered or aromatic aldehydes react via a mechanism that appears to be mainly Zr-catalyzed, based on both the difference in rate between Zr- and Si-mediated reactions as well as differences in enol silane/silyl triflate reactivity in crossover-type experiments. With sterically hindered aldehydes in dichloromethane or nitromethane, catalysis is mediated by Si. The Zr-catalyzed process occurs via formation of a Zr-aldolate complex from aldehyde and enol silane, with liberation of TMSOTf, followed by rate-limiting O-silylation of the metal aldolate by TMSOTf, as revealed by both model studies and in situ monitoring during catalysis.
- Lin, Shuqiong,Bondar, Georgiy V.,Levy, Christopher J.,Collins, Scott
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p. 1885 - 1892
(2007/10/03)
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- Reaction of Trimethylsilyl Benzhydryl Ethers with Methyl N-(Trimethylsilyl)pyroglutamate: An Easy and Rapid N-Alkylation
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In the presence of a small amount of catalyst (mainly triflic acid), methyl N-(trimethylsilyl)pyroglutamate quickly reacts with benzhydryl chlorides or preferentially with trimethylsilyl benzhydryl ethers to give methyl N-(benzhydryl)pyroglutamates in nearly quantitative isolated yields.
- Rigo, Beno?t,Gautret, Philippe,Legrand, Anne,Hénichart, Jean-Pierre,Couturier, Daniel
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p. 998 - 1000
(2007/10/03)
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- Improved preparation of N-trimethylsilylpyridinium triflate, N- triphenylsilylpyridinium triflate, N-triisopropylsilylpyridinium triflate and their use in silylating alcohols to silyl ethers
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N-Silylpyridinium triflates 1a-c have been prepared in excellent yield from the corresponding allyl silanes by reaction with triflic acid followed by pyridine. Compounds 1a-c were used to prepare silyl ethers from alcohols in generally high yield. A convenient procedure has been developed which enables the silylation of alcohols without an aqueous workup in the product isolation.
- Olah, George A.,Klumpp, Douglas A.
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p. 744 - 746
(2007/10/03)
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- Ionic Hydrogenation of Alkynes by HOTf and Cp(CO)3WH
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Alkynes can be hydrogenated at room temperature by an ionic hydrogenation method using triflic acid (CF3SO3H) as the proton donor and a transition metal hydride (Cp(CO)3WH) as the hydride donor.Reaction of PhCCH with HOTf and Cp(CO)3WH gives ethylbenzene as the final product in high yield.Intermediate observed in this reaction are the vinyl triflate CH2=C(Ph)(OTf) and the geminal ditriflate Ph(CH3)C(OTf)2, which result from the addition of 1 or 2 equiv of HOTf to the CC triple bond of the alkyne.Hydrogenation of PhCCMe by HOTf and Cp(CO)3WH similarly produces propylbenzene as the ultimate product.Along with vinyl triflates, additional intermediates observed in this reaction were the cis and trans isomers of the β-methylstyrene complex 2-PhHC=CHCH3)>(+)(-).Hydrogenation of n-butylacetylene to n-hexane does occur upon reaction with HOTf/Cp(CO)3WH, but is very slow.In the absence of metal hydrides, 2-methyl-1-buten-3-yne reacts with HOTf to give the vinyl triflate CH2=CMeC(OTf)=CH2, but reaction with HOTf and Cp(CO)3WH gives Me2C=C(OTf)Me.The key characteristics required for the metal hydride used in these hydrogenations are the ability to donate hydride in the presence of strong acid, and the absence of rapid decomposition of the hydride through reaction with the strong acid.Cp(CO)3WH meets these requirements, but HSiEt3, while an effective hydride donor, is decomposed by HOTf on the time scale of these alkyne hydrogenation reactions.
- Luan, Li,Song, Jeong-Sup,Bullock, R. Morris
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p. 7170 - 7176
(2007/10/03)
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- Esters of (Hydroxymethyl)diorganylsilanes: Synthesis and Thermally Induced Rearrangement
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Twenty silanes of the type R1R2Si(H)CH3OR3 (A) were synthesized 1,R2 = Me, Ph, 1-naphthyl, PhCH2, Me3SiCH2; OR3 = OC(O)Me, OC(O)CF3, OS(O)CF3, OP(O)Ph2, OC(O)Cl> and studied for their thermal behaviour.The silanes A undergo a thermally induced rearrangement to give the corresponding silanes R1R2Si(OR3)Me (B).For compounds with OR3 = OC(O)Cl, an additional decarboxylation takes place to yield the chlorosilanes R1R2Si(Cl)Me.Except for the derivatives with OR3 = OC(O)Cl, the energetic (reaction enthalpy) and kinetic data (reaction order, frequency factor, enthalpy and entropy of activation) of these reactions were studied by means of differential scanning calorimetry (DSC).In addition the kinetics of all reactions were investigated by 1H-NMR spectroscopy.The transition state of the rearrangement was investigated by an ab initio study based on the model compound H3SiCH2OC(O)H MeH2SiOC(O)H>.The theoretical data and the experimentally obtained energetic and kinetic data are discussed in terms of mechanistic aspects of the rearrangement reaction A -> B.
- Tacke, Reinhold,Wiesenberger, Frank,Becker, Beate,Rohr-Aehle, Regine,Schneider, Petra B.,et al.
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p. 591 - 606
(2007/10/02)
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- Reaction of μ-Oxobis with Group 14 Propargyl Derivatives and a Propargyl Ether
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The treatment of 4,4-dimethyl-1-(trimethylsilyl)-2-pentyne (4a) or 4,4-dimethyl-1-(tributylstannyl)-2-pentyne (4b) with μ-oxobis (2) gives 4,4-dimethyl-1-(2-iodophenyl)-2-pentyne (9).Deuterium labeling has confirmed that propargylation of 2 occurs ortho to the position originally occupied by the I(III).The addition of 2 equiv of 4a to 2 at -80 deg C results in 2 equiv of 9, trimethylsilyl triflate (10), and tert-butylallene (11) and 1 equiv of hexamethyldisiloxane (12); in contrast, the addition of 2 equiv of 4b to 2 at -30 deg C results in 2 equiv each of 9 and tributylstannyl triflate (16).A mechanism that explains these product ratios is proposed.The reaction of 2-o,o'-d2 and 4b shows the negligible intramolecular kinetic isotope effect (0.99 +/- 0.01) expected for what is in effect a Claisen rearrangement.The addition of 2 to 2-butynyl (trimethylsilyl)methyl ether (20) affords the single product 21 resulting from anti addition and control of regiochemistry by the ether oxygen.Attempts to desilylate 21 to an allenyl triflate result in the regeneration of the propargyl ether 20.
- Gately, Daniel A.,Luther, Thomas A.,Norton, Jack R.,Miller, Mary M.,Anderson, Oren P.
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p. 6496 - 6502
(2007/10/02)
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- Silylstannylation of ethyl diazoacetate with novel silylstannyl triflates
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Reaction of Ph2tBuSiSnMe3 or iPr3SiSnMe3 with triflic acid (CF3SO3H; TfOH) at -40 deg C yields the first silylstannyl triflates, Ph2tBuSiSnMe2OTf and iPr3SiSnMe2OTf.The former triflate is thermally unstable above 0 deg C, but the latter has been isolated as a thermally stable crystalline solid.Both triflates can be used for efficient silylstannylation of ehtyl diazoacetate.
- Fronda, Antonio,Maas, Gerhard
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p. 289 - 294
(2007/10/02)
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- PHOSPHENIUM CATIONS/IMINOPHOSPHANE REACTIONS. SYNTHESIS OF A SPIRANIC AZADIPHOSHIRANIUM CATION
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The unexpected synthesis of the first spiranic azadiphosphiranium cation is reported, as well as a new entry to diazadiphosphetidine systems.
- Roques, Christian,Mazieres, Marie-Rose,Majoral, Jean-Pierre,Sanchez, Michel
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p. 4547 - 4550
(2007/10/02)
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- Anhydrides of Phosphorus and Sulfur Acids, 2. Mixed Anhydrides of Phosphoric, Phosphonic, and Phosphinic Acids with Sulfonic Acids and Sulfuric Monoimidazolide. New Methods of Synthesis, Novel Structures, Phosphorylating Properties
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New applications of methods leading to anhydrides RR'P(O)OSO2R'' (1) are described: a) Reaction of acids RR'P(O)OH (2) with sulfonic imidazolides. b) Reaction of phosphorus imidazolides 4 with sulfonic acids and sulfonic anhydrides.New methods of synthesis of anhydrides 1 have been developed. c) Reaction of phosphorus acid silyl esters RR'P(O)OSiMe3 (9) with methanesulfonic and trifluoromethanesulfonic anhydrides. d) Reaction of bis(trimethylsilyl) tert-butylphosphonate (10) with methanesulfonic acid leading to tBuP(O)(OSO2Me)2 (11). e) Reaction of stannyl phosphate (EtO)2P(O)OSnMe3 (15) with methanesulfonic anhydride. f) Reaction of phosphorus acid silyl esters 9 with trimethylsilyl trifluoromethanesulfonate.All methods result in high yields and can be adapted to a variety of anhydrides 1 derived from phosphoric, phosphonic, and phosphinic acids on the one hand and methanesulfonic, trifluoromethanesulfonic acids and sulfuric monoimidazolide on the other.Phosphonium intermediates have been demonstrated by low temperature FT 31P NMR spectroscopy for reaction b) and c).The anhydrides 1 are readily converted into imidazolides 4 by the reaction with N-(trimethylsilyl)imidazole which proceeds via two distinct phosphonium intermediates.With neutral and weakly basic nucleophiles, the anhydrides 1 behave as phosphorylating agents.
- Dabkowski, Wojciech,Michalski, Jan,Skrzypczynski, Zbigniew
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p. 1809 - 1824
(2007/10/02)
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- A New in situ Preparation of Trimethylsilyl Trifluoromethanesulfonate by Thermally Induced Rearrangement
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A new in situ preparation of trimethylsilyl trifluoromethanesulfonate (3) is described: 3 is generated by a thermally induced rearrangement of (dimethylsilyl)methyl trifluoromethanesulfonate (2), which can be prepared by reaction of (CH3)2Si(H)CH2OH (1) with (CF3SO2)2O.Starting with C6H5(CH3)Si(H)CH2OH (5), the derivative (methylphenylsilyl)methyl trifluoromethanesulfonate (6) can be obtained by a similar method.Its thermally induced rearrangement leads to dimethylphenylsilyl trifluoromethanesulfonate (7).The rearrangements 2 to 3 and 6 to 7 were found to be first-order reactions with half-lifes at 80 deg C of 0.75 and 1.7 h, respectively.
- Tacke, Reinhold,Link, Matthias,Zilch, Harald
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p. 4637 - 4640
(2007/10/02)
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- Reagents and synthetic methods. 31. Silylations with N-trimethylsilyl-2-oxazolidinone (TMSO)
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Silylation of ketones, alcohols, mercaptans, and carboxylic acids with N-trimethylsilyl-2-oxazolidinone (TMSO) and triflic acid as catalyst has been described from synthetic and mechanistic points of view.
- Aizpurua, Jesus M.,Palomo, Claudio,Palomo, Antonio L.
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p. 336 - 340
(2007/10/02)
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- A NEW TRIMETHYLSILYL TRIFLATE-CATALYZED 1,3-DIPOLAR CYCLOADDITION LEADING TO PYRROLIDINES
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Pyrrolidines were obtained by a new, trimethylsilyl triflate-catalyzed cycloaddition of an intermediary N-trimethylsilylated methylene-iminium ylide, a 1,3 dipole, to olefinic and acetylenic dipolarophiles.
- Achiwa, Kazuo,Sekiya, Minoru
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p. 2589 - 2592
(2007/10/02)
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- Nucleoside Syntheses, XXII. Nucleoside Synthesis with Trimethylsilyl Triflate and Perchlorate as Catalysts
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The novel Lewis acids (CH3)3SiOSO2CF3 (5), (CH3)3SiOSO2C4F9 (6), and (CH3)3SiClO4 (4) are highly selective and efficient Friedel-Crafts catalysts for nucleoside formation from silylated heterocycles and peracylated sugars as well as for rearrangements of persilylated protected nucleosides.With basic silylated heterocycles these new catalysts give much higher yields of the natural N-1-nucleosides than with SnCl4.
- Vorbrueggen, Helmut,Krolikiewicz, Konrad,Bennua, Baerbel
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p. 1234 - 1255
(2007/10/02)
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