N-Halo amides

HI, or Cdl2 iodofluorination with mixtures of AgF and U and mixtures of N-bromo amides in anhydrous HF give bromofluorination. Bromo-, iodo-, and chlorofluorination have also been achieved by treatment of the substrate with a solution of Br2,12, or an N-halo amide in polyhydrogen fluoride-pyridine while... 

The groups R2N and Cl can be added directly to alkenes, allenes, conjugated dienes, and alkynes, by treatment with dialkyl-V-chloroamines and acids. " These are free-radical additions, with initial attack by the R2NH- radical ion. " N-Halo amides (RCONHX) add RCONH and X to double bonds under the influence of UV light or chromous chloride. " Amines add to allenes in the presence of a palladium catalyst. ... 

The first step is an example of 12-52 and intermediate N-halo amides (69) have been isolated. In the second step, 69 lose a proton to the base. Compound 69 are acidic because of the presence of two electron-withdrawing groups (acyl and halo) on the nitrogen. It is possible that the third step is actually two steps loss of bromide to... 

Alkyl hypochlorites and N-halo amides add to isocyanides to give, after hydrolysis, carbamates and N-acylureas (ureides), respectively.806... 

A similar reaction has been carried out on N-halo amides, which give y-lactones 612... 

Barton Beckwith Goosen/. Chem. Soc. 1965, 181 Petterson Wambsgans/. Am. Chem. Soc. 1964,86, 1648 Neale Marcus Schepers J. Am. Chem. Soc. 1966,88, 3051. For a review of N-halo amide rearrangements, see Neale Synthesis 1971, 1-15. 

W.E. Wales D.J. Nagy, USP 3465674 (1969) CA 71, 103744r(1969) (Expl compns with delayed action are described. They may be used to generate sudden pressure, initiate a mech action, or detonate an expl, particularly where it is desired to have a known short delay betw action and reaction. A series of tests was conducted wherein Ig of an N-halo amide was mixed with a small amt of iso-PrOH and the interval betw mixing and expln measured. Mixts of Ig trichloroiso-cyanuric acid and 0.05, 0.10, and 0.15ml iso-PrOH exploded after 15, 17, and 6 sec, resp Mixts of Ig dichloroisocyanuric acid,... 

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... 

As a class, halonitriles are the most genotoxic of the DBFs studied in mammalian cells [19], and they are third in cytotoxicity, similar to other N-DBPs, halo-amides, and halonitromethanes. 

Glycidic esters can easily be converted to aldehydes (2-40). The reaction has been extended to the formation of analogous aziridines by treatment of an imine with an a-halo ester or an a-halo N,N-disubstituted amide and f-BuOK in the solvent 1,2-dimethoxy-ethane.636 However, yields were not high. Acid-catalyzed Darzens reactions have also been reported.637 See also 6-61. 

Perfluorotetramethylene sulflmides are synthesized by the reaction of lithium amide and pnmary amines with (perfluorotetramethylene)sulfur difluonde [7(5] (equation 13) (Table 6) The products can be oxidized with m-chloroperoxybenzoic acid to the corresponding sulfoximides (equation 13) or can be treated with chlorine or bromine to yield N-halo derivatives [76] The reaction of CF3SF3=NCF3 with nucleophiles takes place by attack of the nucleophile at the positive sulfur center [17] (equation 14)... 

N,N-Dialkyl-oi.-halo amides may be substituted for a.-halo esters in the Reformatsky reaction. The yields of N,N-dialkyl-/3-hydroxyamides compare favorably with those of the corresponding hydroxy esters (cf. method... 

All A-halo compounds can be readily determined by analysis based on their oxidizing action. They liberate two equivalents of iodine from acidified potassium iodide solution almost instantaneously (1 mmole of A-monohalo compound is equivalent to 20 ml of O.In-thiosulfate solution). The liberation of iodine from hydrogen iodide involves production of the amine or amide parent of the halo compound. Sodium sulfite and hydrogen sulfide also reduce N-halo compounds. UV and IR spectroscopic methods have been worked out for determination of JV-halo compounds.399... 

---