N-Fluorination

N-fluorine displacement, 7, 272 1-Azetine, 2-alkoxy-nucleophilic reactions, 7, 271 1-Azetine, 2-aryl-mass spectrometry, 7, 268 nucleophilic reactions, 7, 271 1-Azetine, 2-chIoro-nucleophilic reactions, 7, 271... 

Treatment with sodium hypochlorite or hypobromite converts primary amines into N-halo- or N,N-dihaloamines. Secondary amines can be converted to N-halo secondary amines. Similar reactions can be carried out on unsubstituted and N-substituted amides and on sulfonamides. With unsubstituted amides the N-halo-gen product is seldom isolated but usually rearranges (see 18-13) however, N-halo-N-alkyl amides and N-halo imides are quite stable. The important reagent NBS is made in this manner. N-Halogenation has also been accomplished with other reagents, (e.g., sodium bromite NaBr02) benzyltrimethylammonium tribromide (PhCH2NMe3 Br3"), and NCS. The mechanisms of these reactions involve attack by a positive halogen and are probably similar to those of 12-47 and 12-49.N-Fluorination can be accomplished by direct treatment of amines °° or... 

The C-perfluorodisulfonimide (72) is readily N-fluorinated (Equation (4)) by liquid fluorine <87JA7194, 87JAP8726264>. The N-fluoro derivative (73) is a powerful fluorinating agent of high stability and suitable physical properties. It can be converted back to the imide (72) by ammonia... 

Begue, J.-P. Bonnet-Delpon, D. Kornilov, A. Fischer-Durand. N.,/. Fluorine Chem. 1996.80, 13. 

Ishikawa, N., Fluorine Compounds, Modem Technology and Application, Mir, Moscow (1984), translated from Japanese (edited in Japan 1981). 

Benzotriazole can be chlorinated at N(l) by NaOGl. 1-Chlorobenzotriazole is a rather stable crystalline compound that has found application in organic synthesis as a selective chlorinating reagent and mild oxidant. N-Fluorination of benzotriazole with cesium fluoroxysulfate gives 1-fluorobenzotriazole. 

N-Arylated 1,3-propanesultams 236 (R =Ar, R = H) are efficiently prepared from a Pd-catalyzed cross-coupling reaction with different aryl bromides in the presence of Xantphos <2004TL3305>. N-Fluorinated (-l-)-camphorsultams 237 (X = H, Cl, OMe R = F) have been prepared the corresponding imine 16 and difluoro derivative 238 were formed as by-products. The use of 237 is reported in Section 4.05.12.1 <1998JOC9604>. The syntheses of Ar-(l-alkynyl)-Oppolzer s sultams are reported in Section 4.05.6.3.4. Many examples of acylated Oppolzer s sultams are reported in Section 4.05.12.1. 

Radium combines with most non-metals, including oxy n, fluorine, chlorine, and nitro n. It also reacts with acids with the formation of hydrogen g3S. Radium s chemical properties are of much less interest than its radioactivity, however. 

HA/SET] O Flare, P. A. G., Settle, J. L., Hubbard, W. N., Fluorine bomb calorimetry. Part 14. Enthalpies of formation of the hexafluorides of sulphur, selenium, and tellurium and their thermodynamic properties to 1500°K, Trans. Faraday Soc., 62, (1966), 558-565. Cited on page 164. 

Ethoxy-1,1,1 -trifluoro-3-butene-2-one and 3-trilluoroacetyl-3,4-dihydro-2//-pyran react with phenylhydrazine in ethanol, forming the corresponding trifluoromethyl derivatives of pyrazole (01JFC(107)107). Under the same reaction condition treatment these compound with pentafluorophenyl hydrazine or tetrafluorophenyl hydrazine did not give the expected N-fluorinated phenyl pyrazole, it give undehydrated products—5-hydroxy-1-pentafluorophenyl-5-trifluoromethyl-4,5-dihydropyrazole (the molecular structure was identified by X-ray analysis) (01JFC(107)107) (Scheme 101). 

Maruta, M. Kubota, S. Yoshimura, N. Kitazume, T. Ishikawa, N. Fluorine-containing seven-membered benzoheterocycles derived from hexafluoropropene oligomers. J. Fluorine Chem. 1980, 76(1), 75-88. 

Aclar n. Fluorinated polycarbonate film. Manufactured by Allied Chemical, USA. 

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