330-68-7Relevant academic research and scientific papers
Site-Selective Tertiary Alkyl–Fluorine Bond Formation from α-Bromoamides Using a Copper/CsF Catalyst System
Nishikata, Takashi,Ishida, Syo,Fujimoto, Ryo
, p. 10008 - 10012 (2016)
A copper-catalyzed site-selective fluorination of α-bromoamides possessing multiple reaction sites, such as primary and secondary alkyl?Br bonds, using inexpensive CsF is reported. Tertiary alkyl?F bonds, which are very difficult to synthesize, can be formed by this fluorination reaction with the aid of an amide group. Control experiments revealed that in situ generated CuF2is a key fluorinating reagent that reacts with the tertiary alkyl radicals generated by the reaction between an α-bromocarbonyl compound and a copper(I) salt.
Silver-Promoted Fluorination Reactions of α-Bromoamides
Mizuta, Satoshi,Kitamura, Kanami,Kitagawa, Ayako,Yamaguchi, Tomoko,Ishikawa, Takeshi
supporting information, p. 5930 - 5935 (2021/02/01)
Silver-promoted C?F bond formation in α-bromoamides by using AgF under mild conditions is reported. This simple method enables access to tertiary, secondary, and primary alkyl fluorides involving biomolecular scaffolds. This transformation is applicable to primary and secondary amides and shows broad functional-group tolerance. Kinetics experiments revealed that the reaction rate increased in the order of 3°>2°>1° α-carbon atom. In addition, it was found that the acidic amide proton plays an important role in accelerating the reaction. Mechanistic studies suggested generation of an aziridinone intermediate that undergoes subsequent nucleophilic addition to form the C?F bond with stereospecificity (i.e., retention of configuration). The synthesis of sterically hindered alcohols and ethers by using AgI is also demonstrated. Examples of reactions of α-bromoamides with O nucleophiles are presented.
Substitution-reduction: An alternative process for the [ 18F]N-(2-fluoroethylation) of anilines
Briard, Emmanuelle,Pike, Victor W.
, p. 217 - 232 (2007/10/03)
Substitution of a halo atom (chloro or bromo) in easily prepared N-haloacetyl-anilines with no-carrier added (NCA) cyclotron-produced [ 18F]fluoride ion (18F, t1/2 = 109.8 min; β+ = 96.9%), followed by reduction with borane-tetrahydrofuran (BH3-THF), provides an alternative route to NCA [ 18F]N-(2-fluoroethyl)-anilines. This two-step and one-pot process is rapid (～50 min) and moderately high yielding (～40% decay-corrected radiochemical yield (RCY) overall). In the nucleophilic substitution reaction, 18-crown-6 is preferred to Kryptofix 222 as complexing agent for the solubilization of the counter-ion (K+), derived from an added metal salt, in acetonitrile. Weakly basic potassium bicarbonate is preferred as the added metal salt. Inclusion of a small amount of water, equating to 4-5 molar equivalents relative to 18-crown-6, base or precursor (held in equimolar ratio), is beneficial in preventing the adsorption of radioactivity onto the wall of the glass reaction vessel and for achieving high RCY in the nucleophilic substitution reaction. BH3-THF is effective for the rapid reduction of the generated [18F]N-fluoroacetyl-aniline to the [ 18F]N-(2-fluoroethyl)-aniline. Copyright
Process for generating electrophiles from anions by reaction with electrophilic fluorinating agent
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, (2008/06/13)
A process includes substituting a substituent on a substrate. The process includes reacting a salt of an anionic form of the substituent with an electrophilic fluorination agent to provide an electrophile containing a cationic form of the substituent. The electrophile is then electrophilically substituted on the substrate. In some aspects of the process, the substrate can be an aromatic or a non-aromatic. The process can be used for a variety of reactions having electrophilic mechanisms, including halogenation, thiocyanation and nitration.
N-fluorosulfonimides and their application as fluorinating agents
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, (2008/06/13)
The invention describes N-fluorosulfonimides which are useful as fluorinating agents. The N-fluorosulfonimides are stable, easily synthesized, and allow the introduction of fluorine into organic compounds under mild conditions.
Herbicidal aryl triazolinones
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, (2008/06/13)
Herbicidal compounds of the formula STR1 in which, for example, X is Br, Cl or F; Y is Cl or Br, R2 is CHF2, R3 is CH3, R is alkyl, dialkylamino, carboxymethyl, hydroxy, haloalkyl, or aryl, and R1 is H, Na, lower alkyl or --SO2 R.
Herbicidal aryl triazolinones
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, (2008/06/13)
Herbicidal compounds of the formula STR1 in which, for example, X is Br, Cl or F; Y is Cl or Br, R2 is CHF2, R3 is CH3 R is lower alkyl and R1 is H,Na, lower alkyl or --SO2 R.
