Reacción #1375802

Ecuación de reacción

(-)-(R)α-hydroxybenzeneacetic acid

sodium hydroxide

intermediate 2-a

(±)-6-[(4-chlorophenyl)hydrazinomethyl]-1-methyl-1H-benzotriazole monohydrochloride

ethanol

→

(±)-6-[(4-chlorophenyl)-hydrazinomethyl]-1-methyl-1H-benzotriazole (R)-α-hydroxybenzeneacetate

Rendimiento 163.7%

Disolventes

water

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.STIRRINGThe whole was stirred for 30 min. at 60° C.
2. 2
   Otrothe product was crystallized
3. 3
   workup.ADDITIONby adding some product crystals
4. 4
   Otroobtained in a previous low-scale set-up
5. 5
   workup.STIRRINGThen the whole was stirred for 2 hours at 50° C. and overnight at room temperature
6. 6
   workup.STIRRINGstirred for 1 hour
7. 7
   FiltraciónThe product was filtered off
8. 8
   Lavadowashed with ethanol
9. 9
   Otrodried in vacuo

Procedimiento

To a mixture of 200 g of intermediate 2-a and 479 ml of ethanol at 23° C. was added a solution of 23.94 g of sodium hydroxide in 180 ml of water. After stirring for 10 min. there were added 50.2 g of (-)-(R)α-hydroxybenzeneacetic acid. The whole was stirred for 30 min. at 60° C. and the product was crystallized by adding some product crystals obtained in a previous low-scale set-up. Then the whole was stirred for 2 hours at 50° C. and overnight at room temperature. The reaction mixture was cooled (temp.14° C.) and stirred for 1 hour. The product was filtered off, washed with ethanol and dried in vacuo, yielding 118.8 g (87%) of (±)-6-[(4-chlorophenyl)-hydrazinomethyl]-1-methyl-1H-benzotriazole (R)-α-hydroxybenzeneacetate (1:1) monohydrate (interm. 3-a); diastereomeric excess: 92.6%.

Fuente