- Mutated variants of squalene-hopene cyclase: Enzymatic syntheses of triterpenes bearing oxygen-bridged monocycles and a new 6,6,6,6,6-fusded pentacyclic scaffold, named neogammacerane, from 2,3-oxidosqualene
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Squalene-hopene cyclase (SHC) catalyzes the conversion of acyclic squalene molecule into a 6,6,6,6,5-fused pentacyclic hopene and hopanol. SHC is also able to convert (3S)-2,3-oxidosqualene into 3β-hydroxyhopene and 3β-hydroxyhopanol and can generate 3α-hydroxyhopene and 3α-hydroxyhopanol from (3R)-2,3-oxidosqualene. Functional analyses of active site residues toward the squalene cyclization reaction have been extensively reported, but investigations of the cyclization reactions of (3R,S)-oxidosqualene by SHC have rarely been reported. The cyclization reactions of oxidosqualene with W169X, G600F/F601G and F601G/P602F were examined. The variants of the W169L generated new triterpene skeletons possessing a 7-oxabicyclo[2.2.1]heptane moiety (oxygen-bridged monocycle) with (1S,2S,4R)- and (1R,2S,4S)-stereochemistry, which were produced from (3R)- and (3S)-oxidosqualenes, respectively. The F601G/P602F double mutant also furnished a novel triterpene, named neogammacer-21(22)-en-3β-ol, consisting of a 6,6,6,6,6-fused pentacyclic system, in which Me-29 at C-22 of the gammacerane skeleton migrated to C-21. We propose to name this novel scaffold neogammacerane. The formation mechanisms of the enzymatic products from 2,3-oxidosqualene are discussed.
- Fukuda, Yoriyuki,Watanabe, Takashi,Hoshino, Tsutomu
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- Cloning, expression analysis and functional characterization of squalene synthase (SQS) from tripterygium wilfordii
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Celastrol is an active triterpenoid compound derived from Tripterygium wilfordii which is well-known as a traditional Chinese medicinal plant. Squalene synthase has a vital role in condensing two molecules of farnesyl diphosphate to form squalene, a key precursor of triterpenoid biosynthesis. In the present study, T. wilfordii squalene synthase (TwSQS) was cloned followed by prokaryotic expression and functional verification. The open reading frame cDNA of TwSQS was 1242 bp encoding 413 amino acids. Bioinformatic and phylogenetic analysis showed that TwSQS had high homology with other plant SQSs. To obtain soluble protein, the truncated TwSQS without the last 28 amino acids of the carboxy terminus was inductively expressed in Escherichia coli Transetta (DE3). The purified protein was detected by SDS-PAGE and Western blot analysis. Squalene was detected in the product of in vitro reactions by gas chromatograph-mass spectrometry, which meant that TwSQS did have catalytic activity. Organ-specific and inducible expression levels of TwSQS were detected by quantitative real-time PCR. The results indicated that TwSQS was highly expressed in roots, followed by the stems and leaves, and was significantly up-regulated upon MeJA treatment. The identification of TwSQS is important for further studies of celastrol biosynthesis in T. wilfordii.
- Zhang, Bin,Liu, Yan,Chen, Mengmeng,Feng, Juntao,Ma, Zhiqing,Zhang, Xing,Zhu, Chuanshu
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- Enzymic products of the 2,3-oxidosqualene analog having an ethyl residue at 10-position. First trapping of the trimethylcyclohexanone ring by lanosterol synthase
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Incubation of squalene analog, (3RS)-(6E,10E,14E,18E)-10-ethyl-2,6,19,23-tetramethyl-2,3-epoxytetracosa-6, 10,14,18,22-pentaene with 2,3-oxidosqualene-lanosterol cyclase from pig liver gave four products, consisting of two mono-, one tri- and one tetracyc
- Hoshino, Tsutomu,Sakai, Yoshiyuki
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- Squalene Synthetase. Inhibition by Ammonium Analogues of Carbocationic Intermediates in the Conversion of Presqualene Diphosphate to Squalene
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Squalene synthetase (EC 2.5.1.21) catalyzes the formation of squalene (3) from farnesyl diphosphate (1) via presqualene diphosphate (2) in two steps.The mechanism of the rearrangement of 2 to 3 was studied with stable ammonium analogues 6 and 7 of primary and tertiary cyclopropylcarbinyl cations 4 and 5, respectively, proposed as intermediates.In non-pyrophosphate-containing buffers, 6 and 7 were not inhibitors.However, the combination of 6 or 7 with PPi produced potent synergistic inhibition of squalene synthesis from 1 and 2.Amino acid 8, an analogue in whicha phosphonophosphate moiety was tethered to the amino group in 6, was a potent inhibitor of squalene synthesis in pyrophosphate-free buffers.When synthesis of 2 and 3 from 1 was measured simultaneously in the presence of 8, both rates were depressed in an identical manner.It was concluded that squalene synthetase has a single active site which catalyzes 1 --> 2 and 2 --> 3.The mechanism of the second reaction is discussed.
- Poulter, C. Dale,Capson, Todd L.,Thompson, Michael D.,Bard, Ronda S.
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- ent-Kaurene and squalene synthesis in Fusarium fujikuroi cell-free extracts
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Sterols and gibberellins are the main terpenoids in the Ascomycete Fusarium fujikuroi. Their respective precursors squalene and ent-kaur-16-ene (henceforth called kaurene) were the main terpenoids synthesised from radioactive mevalonate by extracts of F. fujikuroi in vitro. Kaurene predominated when the extracts were obtained from mycelia engaged in gibberellin production. Squalene predominated in all other cases, and particularly when the extracts were obtained from mutants with various defects in gibberellin synthesis or nitrogen-fed wild-type cultures. New protein synthesis was required to maintain the production of gibberellins in vivo and of kaurene in vitro, but not to maintain the capacity to produce squalene in vitro. Addition of a nitrogen source to cultures engaged in gibberellin production caused a large, transient increase in the mycelial concentration of L-glutamine and abolished the accumulation of gibberellins immediately and the capacity to produce kaurene later. (C) 2000 Elsevier Science Ltd.
- Fernandez-Martin, Rafael,Domenech, Carlos,Cerda-Olmedo, Enrique,Avalos, Javier
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- Reductive coupling of terpenic allylic halides catalyzed by Cp 2TiCl: A short and efficient asymmetric synthesis of onocerane triterpenes
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(Chemical Equation Presented) Titanocene chloride catalyzes the regioselective α,α′-homocoupling of terpenic allylic halides. This process has been employed in the short and effective synthesis of terpenoids such as β-onoceradiene (1), β-onocerin (2), and squalene (3). Evidence is presented for η1-allyltitanium species being involved in the coupling.
- Barrero, Alejandro F.,Herrador, M. Mar,Del Moral, Jose F. Quilez,Arteaga, Pilar,Arteaga, Jesus F.,Piedra, Maria,Sanchez, Elena M.
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- PALLADIUM-CATALYZED COUPLING OF ALLYLIC ACETATES WITH ZINC
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Allylic acetates were coupled with zinc dust in the presence of a catalytic amount of to give the corresponding 1,5-dienes under mild conditions in high yields.Significant cosolvent effects were found with methanol or 1,2-ethanediol in tetrahydrofuran.
- Sasaoka, Shin-ichi,Yamamoto, Taku,Kinoshita, Hideki,Inomata, Katsuhiko,Kotake, Hiroshi
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- Hexacarbonylmolybdenum(0)-Catalyzed Reductive Coupling of Allylic Acetates
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The reaction of allylic acetates with zinc in the presence of a catalytic amount of hexacarbonylmolybdenum(0) led to reductive coupling for the formation of a 1,5-diene framework.Reductive coupling of nerolidyl acetate provided squalene and its isomers in high yield.
- Masuyama, Yoshiro,Otake, Kiyotaka,Kurusu, Yasuhiko
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- SYNTHESIS OF E,E-FARNESOL, FARNESYL ACETATE AND SQUALENE FROM FARNESENE VIA FARNESYL CHLORIDE
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The present disclosure provides methods for preparing polyunsaturated hydrocarbons, such as E,E-farnesol, farnesyl acetate and squalene, by base catalyzed addition of a dialkylamine to a 3-methylene-1-alkene, such as farnesene. The present disclosure also provides compositions including one more farnesene derivatives prepared using the disclosed methods.
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- Homocoupling versus reduction of radicals: An experimental and theoretical study of Ti(iii)-mediated deoxygenation of activated alcohols
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A detailed experimental and theoretical study corroborates that the reductive deoxygenation of activated (allylic or benzylic) alcohols with excess Ti(iii) proceeds via an allyl(benzyl)-radical and allyl(benzyl)-Ti, which is protonated, regioselectively in the case of allylic derivatives. The H atom of the newly formed C-H bond in the product originates from the -OH group of the starting material. The deoxygenation of lithium alkoxides or alcohols by using 1.0 mol of Ti(iii) leads to the corresponding dimerization products in good yields. An excellent agreement with the experimental data was obtained by using a reaction kinetics simulator to discriminate between competing reactions.
- Prieto, Consuelo,González Delgado, José A.,Arteaga, Jesús F.,Jaraíz, Martín,López-Pérez, José L.,Barrero, Alejandro F.
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p. 3462 - 3469
(2015/03/18)
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- NUCLEIC ACID MOLECULE
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The invention relates to an isolated nucleic acid molecule encoding a polypeptide capable of producing a triterpenoid hydrocarbon. The invention also relates to the encoded polypeptide, a vector comprising the nucleic acid molecule, a recombinant non-human organism comprising the nucleic acid molecule, and to methods of producing a triterpenoid hydrocarbon or an intermediate of biofuel using the nucleic acid molecule, polypeptide or recombinant organism.
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Page/Page column 19; 20
(2012/06/16)
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- Selective deoxygenation of allylic alcohol: Stereocontrolled synthesis of lavandulol
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Selective deoxygenation of allylic alcohol can be successfully carried out by the formation of alkoxyalkyl ether (EE or MOM), followed by Pd(dppe)Cl 2-catalyzed reduction with LiBHEt3. (+)-S-Lavandulol has been efficiently synthesized by the application of this protocol to the diol derived from the Pb(OAc)4-promoted oxidative ring-opening of (-)-R-carvone. This deoxygenation method is general and selective for allylic alcohols.
- Kim, Hee Jin,Su, Liang,Jung, Heejung,Koo, Sangho
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p. 2682 - 2685
(2011/06/26)
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- Ti/Pd bimetallic systems for the efficient allylation of carbonyl compounds and homocoupling reactions
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The allylation, crotylation and prenylation of aldehydes and ketones with stable and easily handled allylic carbonates is promoted by a Ti/Pd catalytic system. This Ti/Pd bimetallic system is especially convenient for the allylation of ketones, which are infrequent substrates in other related protocols, and can be carried out intramolecularly to yield five- and six-membered cyclic products with good stereoselectivities. In addition, Ti/Pd-mediated reductions and Wuertz-type dimerisation reactions can be readily carried out from allyl carbonates and carboxylates.
- Millan, Alba,Campana, Araceli G.,Bazdi, Btissam,Miguel, Delia,Alvarez De Cienfuegos, Luis,Echavarren, Antonio M.,Cuerva, Juan M.
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experimental part
p. 3985 - 3994
(2011/05/07)
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- Understanding the exceptional hydrogen-atom donor characteristics of water in TiIII-mediated free-radical chemistry
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In recent years solid evidence of HAT reactions involving water as hydrogen atom source have been presented. In this work we demonstrate that the efficiency of titanocene(III) aqua complexes as an unique class of HAT reagents is based on two key features: (a) excellent binding capabilities of water toward titanocene(III) complexes and (b) a low activation energy for the HAT step. The theory has predictive capabilities fitting well with the experimental results and may aid to find more examples of this remarkable radical reaction.
- Paradas, Miguel,Campana, Araceli G.,Jimenez, Tania,Robles, Rafael,Oltra, J. Enrique,Bunuel, Elena,Justicia, Jose,Cardenas, Diego J.,Cuerva, Juan M.
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supporting information; experimental part
p. 12748 - 12756
(2010/10/21)
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- Divergent titanium-mediated allylations with modulation by nickel or palladium
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Palladium and nickel are used in conjunction with titanocene(III) complexes to perform selective allylations of carbonyl compounds and alkenes, respectively. Pd/Ti-catalyzed allylation of ketones proceeds diastereoselectively under mild conditions, wherea
- Campana, Araceli G.,Bazdi, Btissam,Fuentes, Noelia,Robles, Rafael,Cuerva, Juan M.,Oltra, J. Enrique,Porcel, Susana,Echavarren, Antonio M.
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supporting information; body text
p. 7515 - 7519
(2009/03/12)
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- Mild TiIII- and Mn/ZrIV-catalytic reductive coupling of allylic halides: Efficient synthesis of symmetric terpenes
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(Chemical Equation Presented) Two new efficient methods for the regioselective homocoupling of allylic halides using either catalytic Ti III or the combination Mn/ZrIV catalyst have been developed. The regio- and stereoselectivity of the process proved to increase significantly when the Mn/ZrIV catalyst is used as the coupling reagent and when cyclic substituted allylic halides are used as substrates. The use of Lewis acids such as collidine hydrochloride allowed the quantity of catalyst to be lowered up to 0.05 equiv. We have proved the utility of these protocols with the synthesis of different terpenoids such as (+)-β-onoceradiene (1), (+)-β-onocerine (2), squalene (5), and advanced key-intermediates in the syntheses of (+)-cymbodiacetal (3) and dimeric ent-kauranoids as xindongnin M (4a).
- Barrero, Alejandro F.,Herrador, M. Mar,Quilez Del Moral, Jose F.,Arteaga, Pilar,Arteaga, Jesus F.,Dieguez, Horacio R.,Sanchez, Elena M.
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p. 2988 - 2995
(2007/10/03)
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- Method for producing squalene
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A process for making squalene involving: (a) providing a hydrocarbon-containing intermediate product derived from a vegetable oil; (b) providing an extractant; and (c) extracting squalene-containing starting material from the hydrocarbon-containing intermediate product to form a squalene-containing raffinate phase and an extract phase.
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- Method of manufacturing squalenes
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Recovery of squalene (I) comprises extracting intermediates (II) containing hydrocarbon from processing vegetable oils with a compressed gas to concentrate (I) in the raffinate and separate the impurities as extract.
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- Enzymatic cyclization reactions of geraniol, farnesol and geranylgeraniol, and those of truncated squalene analogs having C20 and C25 by recombinant squalene cyclase
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The substrate specificity of squalene-hopene cyclase was investigated using the C10-C25 analogs including naturally occurring substances, e.g. geraniol (C10), farnesol (C15) and geranylgeraniol (C20). No cyclization occurred for geraniol, but a significantly high conversion ratio (64%) was observed for farnesol, yielding the cyclic sesquiterpenes consisting of 6/6-fused bicyclic ring systems. Among them, an attractive compound having C30 was produced, in the structure of which acyclic the farnesol unit is linked to the bicyclic skeleton through ether linkage. Conversion of geranylgeraniol was low (ca. 12%). The squalene analogs having C20 and C25 also were cyclized in yields of ca. 33-36%, but the analogs having the methyl group at C(7) and/or at C(11) underwent no cyclization; the large steric bulk size of C(7)-Me and/or C(11)-Me, which is arranged in α-disposition for all the pre-chair conformation, would have interacted repulsively with the cyclase recognition site near to the C(7) and/or C(11), resulting in no construction of the all-chair conformation inside the reaction cavity. A relatively low yield of geranylgeraniol indicated that a less bulky hydrogen atom must be located at C(14) for the efficient polycyclization reaction. The squalene cyclase shows remarkably broad substrate specificity to accept the truncated analogs having carbon-chain lengths of C15-C25 in addition to C 30.
- Hoshino, Tsutomu,Kumai, Yuko,Kudo, Isao,Nakano, Shin-Ichi,Ohashi, Shumi
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p. 2650 - 2657
(2007/10/03)
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- Highly pure squalane, raw material for pharmaceuticals and cosmetics prepared by using the same and method for producing the same
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Highly pure squalane in which the content of pristane is reduced to 10 wt ppm or less, can be obtained by refining the squalane of animal oil or fat origin through thin film distillation, said highly pure squalane is useful as a raw material for producing cosmetics and medical and pharmaceutical preparations and especially, it is quite effective as a lubricating agent for condoms and as a component of adjuvant composition.
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- Einstufige Synthese von Squalen aus Farnesol unter praebiotischen Bedingungen
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Keywords: Eisensulfid; Praebiotische Synthesen; Squalen; Terpenoide
- Keller, Martin,Hafenbradl, Doris,Stetter, Karl O.,Teller, Gerard,Nakatani, Yoichi,Ourisson, Guy
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p. 2015 - 2017
(2007/10/03)
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- Regio- and Stereoselective Synthesis of 1,5-Dienes Using Allylic Barium Reagents
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The highly α,α' selective and sterocontrolled homocoupling reaction of allylic halides was achieved using barium reagent.The double-bond geometry of the starting allylic chloride was completely retained.The α,α' cross-coupling products were also prepared stereospecifically and regioselectively by this method.
- Yanagisawa, Akira,Hibino, Hiroaki,Habaue, Shigeki,Hisada, Yoshiyuki,Yasue, Katsutaka,Yamamoto, Hisashi
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p. 1263 - 1268
(2007/10/03)
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- Derivatives of long chain fatty alcohols, their uses, particularly as cytotrophic and cytoprotective molecules, and pharmaceutical compositions containing them
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Derivatives of long-chain fatty alcohols, and methods of obtaining them, are provided, as well as pharmaceutical compositions containing derivatives and their uses, in particular in treating or preventing neuro-degenerative illnesses, conditions linked to skin ageing, the phenomena of thrombosis and atherosclerosis, and immune deficiencies.
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- A simple synthetic process for the elaboration of oligoprenols by stereospecific coupling of di-, tri-, or oligoisoprenoid units
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An effective method of allyl-allyl coupling which is position and stereospecific leads in a simple way to oligoprenols from E-allylic halides.
- Corey,Shieh
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p. 6435 - 6438
(2007/10/02)
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- Highly Selective Homocoupling Reaction of Allylic Halides Using Barium Metal
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The highly α,α' selective and stereocontrolled homocoupling reaction of allylic halides was achieved using barium reagent.The double-bond geometry of the starting allylic chloride was completely retained. α,α' Cross-coupling products were also prepared stereospecifically and regioselectively by this method.
- Yanagisawa, Akira,Hibino, Hiroaki,Habaue, Shigeki,Hisada, Yoshiyuki,Yamamoto, Hisashi
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p. 6386 - 6387
(2007/10/02)
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- Carbon-carbon bond formation by O→C rearrangement of allylideneoxyphosphoranes
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A new O→C rearrangement reaction, which has been applied to the synthesis of squalene, has been shown to proceed by an intermolecular mechanism.
- De,Corey
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p. 4831 - 4834
(2007/10/02)
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- BIOSYNTHESIS OF UNUSUAL ACYCLIC ISOPRENOIDS IN THE ALGA BOTRYOCOCCUS BRAUNII
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A 'resting state' isolate of the hydrocarbon-producing alga Botryococcus braunii photoassimilated sodium 14C>bicarbonate at rates comparable to fast growing algae, such as Chlorella ( > 150 μg atoms 14C/mg chlorophyll hr).Early in the reaction (up to several min), most of the radioactivity was associated with water-soluble metabolites.However, labeling of hexane-soluble compounds steadily increased from ca 3 percent at 15 sec to over 50 percent of the total incorporated 14C at 60 min.The purified hexane fraction, which consisted of a series of botryococcenes and squalene, constituted a relatively constant proportion (40-45percent) of the total hexane-soluble radioactivity at all bur the earliest time points ( a C30 botryococcene (ca 91 percent) and squalene (ca 8 percent); however, small amounts of radioactivity sequentially appeared in the C31, C32 and C34 botryococcenes.The results of pulse-chase experiments implicated the C30 botryococcene as the precursor of the higher homologues; during the chase, loss of radioactivity from the C30 compound was accompanied by a concomitant increase in the labelling of the C31 and C32 compounds.This study provides further evidence that the relatively slow growth of Botryococcus in culture may result, in part, from the diversion of a large proportion of reduced carbon into energetically expensive compounds and that the slower growth rate in the 'resting state' cannot be totally attributed to an impaired or intrinsically slow metabolism. - Key Wor Index - Botryococcus braunii; Chlorophyceae; alga; biosynthesis acyclic isoprenoids; botryococcenes.
- Wolf, Fred R.,Nemethy, Esther K.,Blanding, Jonathan H.,Bassham, James A.
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p. 733 - 738
(2007/10/02)
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- PALLADIUM-CATALYZED REGIO- AND STEREOSELECTIVE DESULFONYLATION OF ALLYLIC SULFONES WITH LiHBEt3. APPLICATION TO THE SYNTHESIS OF SQUALENE
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Allylic p-tolyl sulfones were easily desulfonylated to the corresponding alkenes by LiHBEt3 in the presence of a catalytic amount of under mild conditions with the preservation of the original stereochemistry.This reaction was successfully applied to the synthesis of squalene.
- Mohri, Mitsunobu,Kinoshita, Hideki,Inomata, Katsuhiko,Kotake, Hiroshi
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p. 451 - 454
(2007/10/02)
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- Complexes η3-allylpalladium : isomerisation et photolyse ; synthese du squalene
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Complexation of primary allylic chlorides in the presence of Pdo may lead to a mixture of syn and anti η3-allylpalladium complexes.Photolysis or thermolysis also causes syn-anti isomerisation.A mixture of squalene stereoisomers is obtained by photolysis of the η3-farnesylpalladium complexes.
- Muzart, J.,Pete, J. P.
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- Reaction of Organic Halides with Chlorotris(triphenylphosphine)cobalt(I)
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Reaction of various types of organic halides with a monovalent cobalt complex, chlorotris(triphenylphosphine)cobalt(I) is described.Reaction of benzylic monohalides, dihalides and trihalides with CoCl(Ph3P)3 gave a coupling product with formation of a carbon-carbon single bond, double bond and triple bond, respectively, under mild and non-basic conditions.Dehalogenation of non-benzylic vicinal dihalides with the reagent took place cleanly to give an olefin in high yield.Reductive coupling of allylic halides using the reagent afforded regioselectively a 1,5-diene with retention of the stereochemistry of the carbon-carbon double bond of the allylic halides used.By using this reaction, (E,E,E,E)-squalene was stereospecifically synthesized from (E,E)-farnesyl bromide.Reaction of halohydrins with CoCl(Ph3P)3 gave exclusively a ketone in the presence of an amine or olefin through an alkylcobalt intermediate.A 1,2-hydrogen shift is involved in this reaction.Keywords - chlorotris(triphenylphosphine)cobalt(I); coupling reaction; benzylic halides; allylic halides; synthesis of 1,5-diene; squalene; halohydrin; ketone synthesis.
- Momose, Den-ichi,Iguchi, Kazuo,Sugiyama, Toshikazu,Yamada, Yasuji
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p. 1840 - 1853
(2007/10/02)
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- REDUCTIVE COUPLING OF ALLYLIC HALIDES BY CHLOROTRIS(TRIPHENYLPHOSPHINE)COBALT(I)
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Reactions of geranyl and farnesyl halide, and their geometrical isomers with chlorotris(triphenylphosphine)cobalt(I) gave the corresponding geometrically pure coupling products under mild and non-basic conditions.Squalenes were stereospecifically synthesized by this method.
- Momose, Den-ichi,Iguchi, Kazuo,Sugiyama, Toshikazu,Yamada, Yasuji
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p. 921 - 924
(2007/10/02)
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- Ring Opening of Oxiranes by Trimethylsilyl Trifluoromethanesulfonate
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Trimethylsilyl trifluoromethanesulfonate promotes ring opening reactions of oxirane derivatives.The reaction course is highly affected by the structures and substitution pattern of the substrates.Tetra-, tri, and 2,2-disubstituted oxiranes and simple cycloalkene oxides are converted to the corresponding allylic alcohol trimethylsilyl ethers.The overall transformation is interpreted in terms of trans addition of the silyl trifluoromethanesulfonate to the oxirane ring followed by base-promoted anti elimination of a trifluoromethanesulfonic acid element. 2,3-dialkyl- or monoalkyloxiranes isomerize to the corresponding ketones and aldehydes, respectively. (Z)-Cyclooctene oxide undergoes the transannular reaction to give endo-cis-2-trimethylsiloxybicyclooctane.The reaction of 6-methyl-5-hepten-2-one oxide produces 2,2,6-trimethyl-3-trimethylsiloxy-3,4-dihydro-2H-pyran. 1,2-Methyl migration takes place in the reaction of (E)-3α-t-butyldimethylsiloxy-5α-pregnene 17α,20-oxide to afford 3α-t-butyldimethylsiloxy-17β-methyl-17α--18-nor-5α-androst-13(14)-ene. α-Pinene oxide gives trans-carveol trimethylsilyl ether.
- Murata, Sizuaki,Suzuki, Masaaki,Noyori, Ryoji
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p. 247 - 254
(2007/10/02)
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- TRIMETHYLSILYL TRIFLATE IN ORGANIC SYNTHESIS
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Trimethylsilyl triflate is a powerful silylating agent for organic compounds and acts as a catalyst which accelerates a variety of nucleophilic reactions in aprotic media.The reactions proceed via one-center, electrophilic coordination of the silyl group to hetero functional groups and exhibit unique selectivities.
- Noyori, R.,Murata, S.,Suzuki, M.
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p. 3899 - 3910
(2007/10/02)
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