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Fluorination Reagents, Fluorinated Building Blocks

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Fluorination Reagents, Fluorinated Building Blocks The list of products We introduce our products according to their applications and their structure. Fluorinating Agents ・・・・・・・・・・ 7 Difluoro Aromatic Hydrocarbons ・・・・・・ 27 1,2-Difluorobenzenes ・・・・・・・・・・・・・・・・ 27 Electrophilic Fluorinating Agents・ ・・・・・・ 7 1,3-Difluorobenzenes ・・・・・・・・・・・・・・・・ 29 Nucleophilic Fluorinating Agents・ ・・・・・・ 7 1,4-Difluorobenzenes ・・・・・・・・・・・・・・・・ 32 Trifluoro Aromatic Hydrocarbons ・・・・・・ 32 Difluoromethylating Agents ・・・・・・ 7 1,2,3-Trifluorobenzenes ・・・・・・・・・・・・・・・ 32 1,2,4-Trifluorobenzenes ・・・・・・・・・・・・・・・ 33 Trifluoromethylating Agents ・・・・・・ 8 1,3,5-Trifluorobenzenes ・・・・・・・・・・・・・・・ 34 Polyfluoro Aromatic Hydrocarbons ・・・・・ 34 Trifluoromethylthiolating Agents ・・・・ 8 Tetrafluorobenzenes ・・・・・・・・・・・・・・・・・ 34 Pentafluorobenzenes ・・・・・・・・・・・・・・・・ 35 Other Polyfluoro Aromatic Hydrocarbons ・・・・・・・ 37 Perfluoroalkylating Agents ・・・・・・・ 9 Difluoromethyl / Difluoromethoxy Aromatic Hydrocarbons ・・・・・・・・・・・ 37 Other Fluorinated Group Introducing Trifluoromethyl Aromatic Hydrocarbons ・・・ 38 Agents ・・・・・・・・・・・・・・・・ 9 Monosubstituted (ortho-) Trifluoromethylbenzenes ・・ 38 Monosubstituted (meta-) Trifluoromethylbenzenes ・・・ 38 Monosubstituted (para-) Trifluoromethylbenzenes ・・・ 40 Fluorinated Building Blocks ・・・・・ 10 Disubstituted Trifluoromethylbenzenes ・・・・・・・・ 41 Other Trifluoromethyl Aromatic Hydrocarbons ・・・・・ 43 Monofluoro Aromatic Compounds ・・・・ 10 Monosubstituted (ortho-) Monofluorobenzenes ・・・・ 10 Trifluoromethoxy Aromatic Hydrocarbons ・・ 44 Monosubstituted (meta-) Monofluorobenzenes ・・・・ 11 Trifluoromethylthio Aromatic Hydrocarbons ・ 46 Monosubstituted (para-) Monofluorobenzenes ・・・・ 12 ・・・・・・・ Disubstituted (2,3-) Monofluorobenzenes 16 Pentafluorosulfanyl Aromatic Hydrocarbons ・ 46 Disubstituted (2,4-) Monofluorobenzenes ・・・・・・・ 17 Heteromonocyclic Compounds ・・・・・・・ 46 Disubstituted (2,5-) Monofluorobenzenes ・・・・・・・ 20 Disubstituted (2,6-) Monofluorobenzenes ・・・・・・・ 23 Condensed Heterocyclic Compounds ・・・・ 50 Disubstituted (3,4-) Monofluorobenzenes ・・・・・・・ 23 Aliphatic Compounds ・・・・・・・・・・・・ 51 Disubstituted (3,5-) Monofluorobenzenes ・・・・・・・ 26 Trisubstituted Monofluorobenzenes ・・・・・・・・・ 26 Other Monofluoro Aromatic Hydrocarbons ・・・・・・ 27 Fluorination Reagents, Fluorinated Building Blocks The introduction of fluorine into bioactive molecules often the fluoride anion and this leads to decrease in reactivity. results in significant changes in their chemical, physical, and "Naked" fluoride anions, where the fluoride anion is completely biological properties. Fluorine uniquely affects the property of free of hydrogen bonds, have been developed. For example, organic molecules due to the fluorine atom’s blocking effect in tetrabutylammonium difluorotriphenylstannate [T1592], which metabolic transformations and mimicking of enzyme substrates, was reported by Gingrasas an alternative reagent to Bu4N • F, is and then increases the molecular lipophilicity to enhance non hygroscopic with excellent stability to heat and high solubility bioavailability. Approximately 30% of all agrochemicals and in organic solvents.2) Martines et al. synthesized gem- 20% of all pharmaceuticals contain fluorine.1) HMG-CoA fluorotriflate from aldehyde using T1592.3) reductase inhibitor fluorostatin (atorvastatin), antibiotic fluoroquinolone (levofloxacin), and antitumor fluoronucleoside F Ph (tegafur) are successful examples of the introduction of fluorine n Bu4N Ph Sn into organic molecules (Fig. 1). Therefore, fluorinating agents Ph F are useful tools for the synthesis of pharmaceutical and Tf2O OTf [T1592] F R CHO R CH R CH agricultural compounds. OTf OTf DAST [D1868] is used in a wide variety of synthetic processes O O O O for stereospecifically substituting a fluorine atom for a hydroxyl N F OH F 4) H HN group. Kozikowski et al. have developed the method of CH N 3 N N O N producing (-)-fluoro-myo-inositol from quebrachitol in two CH3 F OH O N O O 5) CH3 CH3 stages. They reported that in this method, D1868 reacts with HO OH either of two axial hydroxyl groups of a quebrachitol to form a Atorvastatin Levofloxacin Tegafur DAST intermediate which greatly increases the leaving ability of Fig. 1 Fluorinated bioactive compounds the hydroxyl group. This enables an easy nucleophilic displacement of the hydroxyl group by the fluoride anion Since there are few naturally occurring fluorine containing accompanied with steric inversion. D1868 is unstable to heat, compounds, it is necessary to fluorinate organic compounds at a and is drastically decomposed by heating. However, in general, certain stage of the syntheses. Though fluorine gas and the reactions using D1868 are completed in a short time at room hydrogen fluoride are used as fluorine sources, they are very temperature or lower temperature. toxic and corrosive and require special equipment and F techniques for handling them. Therefore, alternate fluorinating Et N S F agents have been developed, which are used in laboratories to OH Et OMe F OH OMe OMe F OH OH [D1868] easily introduce a fluorine atom at selected positions of the OH + OH OH F OH OH OH compounds. The fluorinating agents are roughly classified into HO OH HO two categories: nucleophilic and electrophilic. Nucleophilic OH OMe NEt2 - OH F S F F OH fluorinating agents are those where the fluoride anion serves as O OH + O OMe - OH F S F F OH a reaction active species. Electrophilic fluorinating agents are NEt2 HO OH those where the electron-deficient fluorine atom serves as a DAST intermediate OH reaction active species. In addition, a fluorinated building block BBr F 3 HO is used as a fluorine source, which has both a fluorine atom and HO OH OH a replaceable functional group in a molecule. 4-tert-Butyl-2,6-dimethylphenylsulfur trifluoride (FLUOLEAD™) １．Nucleophilic Fluorinating Agents [B3664], which was first reported by Umemoto, is a novel The most basic nucleophilic fluorinating agent is hydrogen nucleophilic fluorinating agent.7) B3664 is a white crystalline fluoride which is used in large quantity for the industrial solid with high thermal stability, which has a 232 °C thermal production of fluorinated compounds. Hydrogen fluoride, decomposition temperature (by DSC analysis). Differing from however, is scarcely used in laboratories due to its toxic and other existing fluorinating agents, such as DAST, B3664 has corrosive properties and its low reactivity resulting from high H-F less fuming character. And the reactivity of B3664 to water is bond energy. Nucleophilic fluorinating agents such as KF, CsF slow, which makes it easier to handle in open air. [C2204], and Bu4N • F [T2754] are readily available. These Fluorinations of a hydroxyl or carbonyl group by B3664 afford fluorinating agents are hygroscopic, and unfortunately the the corresponding fluorinated compounds in good yields under a moisture in these substances forms strong hydrogen bonds with wide range of conditions (0 to 100 °C). Please inquire for pricing and availability of listed products to our local sales representatives. 3 Fluorination Reagents, Fluorinated Building Blocks 9) CH3 to-handle crystal, has high reactivity. The fluorinating ability can CH3 be increased or decreased by introducing electron withdrawing CH3 SF3 groups or electron donating groups into the pyridine ring. For CH 3 example, the fluorinating ability increases in the order of a, b and CH3 c of the structures shown below. Suppression of side reactions OH [B3664] (1.5 eq.) F and improvement in yield are possible by selecting an adequately CH Cl , 0 C°, 0.5 h & rt, 3 h Br 2 2 Br reactive agent for the situation. B3664 (1.9 eq.) EtOH (0.4 eq.) C H CHO C H CF H 5 11 5 11 2 CH3 CH2Cl2, rt, 20 h X XX CH3 N CH3 N Cl N Cl Unlike other fluorinating agents, B3664 can convert carboxyl F F F groups (-COOH) to trifluoromethyl groups (-CF3) in good yields. a b c Furthermore, thioketones or thioesters can be fluorinated by - - - - - - X =BF4 [F0346] X =BF4 [F0343] X =BF4 [F0344] - - B3664. Thus, B3664 is a useful fluorinating agent widely X =CF3SO3 [F0327] applicable to various substrates, and can be an alternative to CH3 other fluorinating agents. CH3 1)LiHMDS,THF,-78°C O OCH3 CH3 CH3 Ph O O B3664 (3 eq.) 2)a,-78°Ctor.t. C7H15 COOH C7H15 CF3 neat, 100 C°, 5 h CH CH S 3 3 F F CH3 F F CH3 O OCH O OCH B3664 (2.5 eq.) 3 3 CH CH CH CH CH2Cl2, rt, 4 h 3 3 + 3 3 Ph O O Ph O O S 3.8:1 B3664 (3 eq.), SbCl3 (5 mol%) C10H21 O SCH3 C10H21 OCF3 CH2Cl2, 0 C° to rt, 1.5 h N-Fluoro-N'-(chloromethyl)triethylenediamine bis(tetrafluoro- Another method for facilitating the attack of fluoride anions is borate) [F0358] is an easily handled powder and versatile achieved by producing carbocations. Carbocations can be electrophilic fluorinating agent for enols, silyl enol ethers, produced by oxidation of organic compounds. Consequently, the alkenes, stabilized carbanions, aromatic compounds, combined use of an oxidizing agent and a fluorinating agent organosulfur compounds, Grignard agents, etc.10) enables easy fluorination. In addition, selective fluorination becomes possible by selecting an oxidizing agent. Kuroboshi et F al. have achieved the synthesis of fluoroiodoalkanes from olefins N - OH SnBu3 2BF4 F using tetrabutylammonium dihydrogentrifluoride [T1635] and N (1.2 eq.) 8) CH Cl [F0358] NIS as oxidizing agent. 1) Triflation 2 2) Stannylation AgOTf (2.0 eq.) Acetone, 23ºC, 20 min Ph Ph Ph nBu N[ H F ] [T1635] 1 2 1 4 4 2 3 R R R R NIS F I 2 3 R R CH2Cl2 R3 N-Fluorobenzenesulfonimide is also an easily R4 [F0335] handled and stable crystalline electrophilic fluorinating agent for enolates, silyl enol ethers,
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