Reacción #9442

Ecuación de reacción

triethyl orthoformate

Meldrum's acid

3-bromoaniline

3-bromoaniline

→

5-[(3-bromophenylamino)methylene]-2,2-dimethyl-[1,3]dioxane-4,6-dione

Disolventes

ethanol

ethanol

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaAfter cooling to 50° C.
2. 2
   Temperaturawas maintained between 50–55° C
3. 3
   workup.ADDITIONwas added
4. 4
   workup.STIRRINGto facilitate stirring
5. 5
   workup.ADDITIONUpon complete addition
6. 6
   Temperaturathe reaction was cooled to room temperature (RT)
7. 7
   Filtraciónthe solids were collected by filtration
8. 8
   LavadoThe filter cake was washed with ice cold ethanol until the washings
9. 9
   Otrothe product was dried at 65° C. under vacuum

Procedimiento

A mixture of triethyl orthoformate (154 grams (g), 1.04 moles (mol) and Meldrum's acid (142 g, 0.983 mol) was heated to 55° C. for 4 hours (h). After cooling to 50° C., a solution of 3-bromoaniline (162.6 g, 0.945 mol) in ethanol (300 mL) was added such that the temperature of the reaction was maintained between 50–55° C. After half of the 3-bromoaniline had been added, stirring became difficult due to the formation of solids, so more ethanol (1 liter (L)) was added to facilitate stirring. Upon complete addition, the reaction was cooled to room temperature (RT), and the solids were collected by filtration. The filter cake was washed with ice cold ethanol until the washings were nearly colorless, and the product was dried at 65° C. under vacuum to afford 287 g of 5-[(3-bromophenylamino)methylene]-2,2-dimethyl-[1,3]dioxane-4,6-dione as an off-white solid.

Fuente