78948-09-1Relevant articles and documents
Two-step regio- and stereoselective syntheses of [19F]- and [18F]-2-deoxy-2-(R)-fluoro-β-D-allose
Ashique, Rezwan,Chirakal, Raman V.,Hughes, Donald W.,Schrobilgen, Gary J.
, p. 457 - 466 (2006)
Replacement of specific hydroxyl groups by fluorine in carbohydrates is an ongoing challenge from chemical, biological, and pharmaceutical points of view. A rapid and efficient two-step, regio- and stereoselective synthesis of 2-deoxy-2-(R)-fluoro-β-d-allose (2-(R)-fluoro-2-deoxy-β-d-allose; 2-FDβA), a fluorinated analogue of the rare sugar, d-allose, is described. TAG (3,4,6-tri-O-acetyl-1,5-anhydro-2-deoxy-d-arabino-hex-1-enitol or 3,4,6-tri-O-acetyl-d-glucal), was fluorinated in anhydrous HF with dilute F 2 in a Ne/He mixture or with CH3COOF at -60°C. The fluorinated intermediate was hydrolyzed in 1 N HCl and the hydrolysis product was purified by liquid chromatography and characterized by 1D 1H, 13C, and 19F NMR spectroscopy as well as 2D NMR spectroscopy and mass spectrometry. In addition, 18F-labeled 2-deoxy-2-(R)-fluoro-β-d-allose (2-[18F]FDβA) was synthesized for the first time, with an overall decay-corrected radiochemical yield of 33 ± 3% with respect to [18F]F2, the highest radiochemical yield achieved to date for electrophilic fluorination of TAG. The rapid and high radiochemical yield synthesis of 2-[18F] FDβA has potential as a probe for the bioactivity of D-allose.
Acetyl Hypofluorite, the First Member of a New Family of Organic Compounds
Rozen, Shlomo,Lerman, Ori,Kol, Moshe
, p. 443 - 444 (1981)
Some sodium salts in acetic acid-Freon 11 (CFCl3) when treated with elemental fluorine produce acetyl hypofluorite, CH3CO2F, a new electrophilic fluorinating agent.
Activation of a CH bond in polypyridine systems by acetyl hypofluorite made from F2
Gatenyo, Julia,Hagooly, Youlia,Vints, Inna,Rozen, Shlomo
, p. 1856 - 1860 (2012)
Activation of the relatively inactive polypyridine backbone with strong electrophilic fluorine, originating from acetyl hypofluorite (AcOF) enables attack of the acetoxy moiety at the α position to the heteroatom. Derivatives of bipyridine, phenanthroline and terpyridine systems have been acetoxylated or oxygenated within a few minutes usually in very good yields.
METHODS AND COMPOUNDS USING IN-LOOP FLUORINATION
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Page/Page column 13-14, (2020/11/12)
This invention provides a novel method that is simple, efficient, and allows for a reliable production of fluorine- 18 (18F) radiofluorinated compounds and radiopharmaceuticals. The method comprises an "in-loop" process, where an 18F
Mono and difluorination of centers α to sulfonates and phosphonates using AcOF
Vints, Inna,Gatenyo, Julia,Rozen, Shlomo
, p. 66 - 69 (2013/03/29)
Acetyl hypofluorite, made easily from diluted fluorine and AcONa is very efficient in fluorinating anionic centers. Compounds containing the moieties CH2SO2 or COCH2PO react with bases to create the corresponding anions wh
Fluorination of aryl boronic acids using acetyl hypofluorite made directly from diluted fluorine
Vints, Inna,Gatenyo, Julia,Rozen, Shlomo
, p. 11794 - 11797 (2014/01/06)
Aryl boronic acids or pinacol esters containing EDG were converted in good yields and fast reactions to the corresponding aryl fluorides using the readily obtainable solutions of AcOF. In reactions with aryl boronic acids containing EWG at the para position, there are two competing forces: one directing the fluorination to take place ortho to the boronic acid and the other, toward an ipso substitution. With EWG meta to the boronic acid, substitution ipso to the boron moiety takes place in good yields.
Synthesis of α-fluorocarboxylates from the corresponding acids using acetyl hypofluorite
Rozen,Hagooly,Harduf
, p. 7464 - 7468 (2007/10/03)
α-Fluorocarboxylic esters and acids were synthesized in good yields. The corresponding esters and acids were converted to their ketene acetals, and these enol derivatives reacted with AcOF made directly from fluorine. This route circumvents the problems associated with nucleophilic fluorinations such as various eliminations and rearrangements. α- and β-branched carboxylic acid derivatives that cannot be directly fluorinated gave by this electrophilic fluorination the corresponding α-fluoro derivatives in good yield. Both the fluorination reaction and the preparation of AcOF are fast and suitable for [18]F incorporation into acids and esters needed for working with PET. α-Fluoroibuprofen (20) and methyl 2-fluoro-3,3,3-triphenylpropionate (32) are two examples of this general reaction.
Fluorination of Nitro Compounds with Acetyl Hypofluorite
Rozen, Shlomo,Bar-Haim, Arie,Mishani, Eyal
, p. 6800 - 6803 (2007/10/02)
Various types of nitro derivatives are fluorinated to form the CFNO2 moiety in very good yields using acetyl hypofluorite (AcOF).The corresponding nitro anion, preferably prepared with NaOMe, is added quickly to a cold (-75 deg C) CFCl3 solution of AcOF,
Chemistry of Oxaziridines. 18. Synthesis and Enantioselective Oxidations of the oxaziridines
Davis, Franklin A.,Weismiller, Michael C.,Murphy, Christopher K.,Reddy, R. Thimma,Chen, Band-Chi
, p. 7274 - 7285 (2007/10/02)
The synthesis and enantioselective oxidations of oxaziridines 13 are reported.These reagents are prepared in two steps from the (camphorylsulfonyl)imine 4 by treatment of the corresponding azaenolate with electrophilic halogen sources followed by biphasic oxidation of the resulting dihalo imine 6-9 with m-CPBA/K2CO3.Of these oxaziridines the dichloro reagent 13b, available on a multigram scale, affords the highest enantioselectivities for the asymmetric oxidation of sulfides to sulfoxides (42-74 percent) and for the hydroxylation of enolates (often better than 95 percent ee).In general the molecular recognition is predicted and explained in terms of minimization of nonbonded steric interactions in the transition states.For the asymmetric oxidation of sulfides to sulfoxides, secondary electronic factors related to the polarity of the sulfide and oxaziridine also play a role.Definitive evidence for chelation of the metal enolate with the C-X bond in 13 is not found.The molecular recognition is interpreted in terms of the higher reactivity of the reagents and an active-site structure which is sterically complementary with the enolate.For the asymmetric hydroxylation of the Z- and E-enolates of propiophenone (16a), the Z-enolate exhibits much higher stereoselectivity than the E-enolate: >95 percent vs 22 percent ee.
Utilizing Acetyl Hypofluorite for Chlorination, Bromination, and Etherification of the Pyridine System
Hebel, David,Rozen, Shlomo
, p. 6298 - 6301 (2007/10/02)
Acetyl hypofluorite, which is easily made from F2, possesses a strong electrophilic fluorine.This electrophile is able to attach itself to the nitrogen atom of pyridine and activate the ring toward nucleophilic attacks.The ultimate elimination of HF results in an overall easy nucleophilic displacement of the hydrogen of the important 2-position .The nucleophiles used: Clδ-, Brδ-, ROδ-, originate from solvents such as CH2Cl2, CH2Br2, and various primary alcohols.Thus, 2-halo- or 2-alkoxypyridines were formed.The reaction conditions (room temperature, very short reaction times, and good yields) transform the task of direct substitution of the pyridine ring from an extremely difficult to a very easy procedure.
