
TY  - JOUR
A1  - Curtis, NJ 
T1  - N-Alkylations and O-Alkylations of Nitro-Substituted 1,3-Diphenylureas: Preparations of Propellant Stabilizer Derivatives
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1988
VL  - 41
IS  - 4
SP  - 585
EP  - 595
KW  - 
UR  - https://doi.org/10.1071/CH9880585 
N2  - A procedure has been developed for the N- ethylation and methylation of 1,3-diphenylureas, ArNRCONHAr&#8242; (R = H, Me or Et), through treatment with sodium hydride and iodoalkane in dimethylformamide. The reaction was general, provided that the aniline to be alkylated was substituted with no more than one nitro group. ArRNCONR&#8242;Ar&#8242; derivatives prepared were: R = R&#8242; = Et (and Me); Ar = phenyl, Ar&#8242; = 2-nitrophenyl and 4- nitrophenyl ; Ar = 2-nitrophenyl, Ar&#8242; = 2-nitrophenyl and 4-nitrophenyl; Ar = Ar&#8242; = 4-nitrophenyl. Two mixed derivatives were also prepared: R = Et, R&#8242; = Me, Ar = phenyl, Ar&#8242; = 2-nitrophenyl and 4-nitrophenyl. O-Alkylated isourea products were obtained in the reactions of 1-(2,4- dinitrophenyl )-3-(2-nitrophenyl)urea and 1-(2,4-dinitrophenyl)-3-(4- nitrophenyl )urea. The use of potassium carbonate as the base led to apparently exclusive O- alkylation of 1,3-bis(2-nitrophenyl)urea although the reaction was not general. 1-(2,4-Dinitrophenyl)-1,3- diethyl-3-phenylurea was prepared by using silver oxide and obtained as a mixture with the isourea . Many of the compounds prepared are important nitro derivatives of the propellant stabilizers, ethyl and methyl centralite. 
ER  -

