Reacción #6609

Ecuación de reacción

ethyl chloroformate

4-carboxybenzyl 5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthyl ether

triethylamine

sodium borohydride

hydrochloric acid

→

title compound

Rendimiento 37.7%

4-Hydroxymethylbenzyl 5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthyl ether

Rendimiento 37.7%

Disolventes

tetrahydrofuran

tetrahydrofuran

tetrahydrofuran

water

Condiciones de reacción

Tratamiento posterior

1. 1
   Filtraciónthe solid was filtered off
2. 2
   workup.WAITto reach room temperature within 1 h
3. 3
   OtroMost of the tetrahydrofuran was removed in a rotary evaporator
4. 4
   Extracciónthe remaining aqueous phase was extracted with chloroform
5. 5
   SecadoThe organic phase was dried over Na2SO4
6. 6
   Concentraciónconcentrated
7. 7
   OtroFractional crystallization from ethyl acetate

Procedimiento

A solution of 0.97 g (9 mmol) of ethyl chloroformate in 5 ml of tetrahydrofuran was added dropwise to a solution of 3 g (9 mmol) of 4-carboxybenzyl 5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthyl ether and 0.9 g (9 mmol) of triethylamine in 20 ml of dry tetrahydrofuran at 0° C. The mixture was stirred at 0° C for 30 min, the solid was filtered off, and the filtrate was added dropwise to a solution of 0.83 g (22 mmol) of sodium borohydride in 8 ml of tetrahydrofuran and 8 ml of water. The reaction mixture was then allowed to reach room temperature within 1 h and was then acidified with 1N hydrochloric acid. Most of the tetrahydrofuran was removed in a rotary evaporator, and the remaining aqueous phase was extracted with chloroform. The organic phase was dried over Na2SO4 and concentrated. Fractional crystallization from ethyl acetate, discarding the first fraction, resulted in 1.1 g of the title compound of melting point 108°-109° C.

Fuente