1,3-bis(2-methoxyphenyl)urea

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of N,N'-di-(2-methoxyphenyl)-urea (6.81 g, 25 mmol) and tetra-n-butyl-ammoniumbromide (0.4 g, 1.3 mmol) in methylene chloride/methanol (1:1 , 200 ml) was at room temperature under vigorous stirring added a solution of sodium hydroxide (2 g in 10 ml water) followed by a solution of sodiumhypochlorite(55 ml, Aldrich). The mixture was stirred for 4 hours and 30 ml water was added The organic phase was washed with 10 ml 1M hydrogen chloride sol., dried and concentrated in vacuo. Upon trituration with diethyl ether dark grey crystals separated The crude product was recrystallized twice, first from ethanol and then from ethyl acetate yielding the title compound as white crystals, M.p. 246°-247° C. was at room temperature The mixture was stirred for 4 hours was washed with 10 ml 1M hydrogen chloride sol. dried concentrated in vacuo Upon trituration with diethyl ether dark grey crystals separated The crude product was recrystallized twice, first from ethanol

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of o-anisidine (12.3 g, 100 mmol) and triethylamine (11 ml, 80 mmol) in absolute toluene (100 ml) was under stirring on an ice bath added phosgene (20.7 ml, 1.93 M sol in toluene, 40 mmol) and the mixture was stirred at 90° C. for 3 hours. The reaction mixture was after cooling to ambient temperature poured into water (100 ml) and the title compound was collected by filtration and used without further purification. the mixture was stirred at 90° C. for 3 hours the title compound was collected by filtration used without further purification