Chlorourea

Ureas. Chlorination of aqueous urea yields unstable A/-chloro compounds. With excess C10 decomposition yields CO2, N2O, and NCl the latter decomposes further to NO (96). Only two soHd derivatives have been isolated A/-chlorourea [3135-74-8] mp 74—76°C, and N,lSf-dichlorourea [2959-01-5] which decomposes at its mp of 83°C with evolution of NCl. As an amide, urea also undergoes the Hofmann reaction yielding hydrazine. This route to hydrazine was once employed commercially. 

Various substituted N-hiomo- and A/-chloroureas have also been prepared (97). These compounds are useful for synthesis of oxazoUdinones, and also hydrazine, hydrazo, and azo compounds. A/-Bromourea [51918-81 -1] is useful for selective oxidation of sugar derivatives (98). 

Pytlewski, L. L Rep. AD-A028841, 13, Richmond (Va.), USNTIS, 1976 Contact of gaseous ammonia with the /V-chlorourea. either alone, or mixed with zinc oxide, leads to ignition. The same could happen in contact with cone, aqueous ammonia, solid ammonium carbonate or organic amines. 

One-electron reduction of A-chlorohydroxamic esters to give alkoxyamidyls, which dimerize to 8, has been observed in ethanol with triethylamine as reductant . Carbamyl derivatives (3b) react analogously in methanol as do A-alkoxy-A-chloroureas (3a) in benzene . 

Af-Acyloxy-Al-alkoxyureas and carbamates (equation 9, R = NR2, RO) have been generated similarly in MeCN . Earlier, the same group described the synthesis of N,N-dialkoxyureas (76) from the reaction of Al-alkoxy-V-chloroureas (75) with sodium alkox-ides in the corresponding alcohol (equation 10) Properties of Af,Af-dialkoxyamides and -ureas and -carbamates are described in Section V. 

V-Alkoxy-V-chloroureas (77) have also been reacted with nitrogen nucleophiles resulting in Sat2 displacement of chloride. The products suggest that the reaction proceeds via an unstable V-alkoxy-V-amino intermediate (78), which under the influence of hydrochloric acid formed in the reaction, decomposed as illustrated to diaminomethane (79) and urea (80) (Scheme 15), although the exact mechanism is unclear . 

The 3,7-dione (589) results from the elimination of hydrogen chloride from the chlorourea derivative (588) (29BSF1013). 

Carbomethoxybenzaldehyde, 100 Carbon disulfide, 57 Chlorine, 24 Chloroacetamide, 22 Chloroacetonitrile, 22 Chlorobenzene, 96 lra i-2-CHLOROCYCLOPENTANOL, 24 2-Chloroethyl benzoate, 11 Chloromethylation, 68 1-Chloromethylnaphthalene, 67, 68 Chlorourea, see Monochlorourea Choline, chloride benzoate, 10 Choline, iodide benzoate, 10 Cinnamaldehyde, 75, 77 Cleavage of tetrahydrofuran, 27, 33 Condensation, of aniline and triphenyl carbinol, 5... 

ETHYL ETHER, 34, 16, 49 Chlorourea, see Monochlorourea (3-ChloroviNYL isoamyl ketone, 32, 27, 79... 

Ring closure. Di-f-butyldiaziridinone (3), a new three-membered ring heterocycle, has been prepared from 1,3-di-r-butylurea (1) by chlorination (2, f-butyl hypochlorite) followed by ring closure with potassium /-butoxide in /-butanol.2 The overall yield is 90%. The intermediate 1-chlorourea can be isolated, but improved yields are obtained without isolation. Use of potassium metal in pentane lor the cyclization step lowered the yields to 48%. Apparently the two alkyl... 

Chlorourea can also be used to add HOC1 to C=C bonds.300 Chlorourea301 [m.p. 71° (dec.)] dissolves in ca. 5 parts of water it is best handled in solution explosions can occur during chlorination of urea (formation of nitrogen trichloride). 

N-Halogenamides N-Bromoacetamide N, N-Dichlorurethan Methyl N-dichloro-carbamate Chlorourea... 

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