Reacción #76261

Ecuación de reacción

NH4Cl

Methanol

LiBH4

ethyl 6-bromo-2-methyl-2-p-tolyl-hexanoate

→

6-bromo-2-methyl-2-p-tolyl-hexan-1-ol

Rendimiento 96.2%

Disolventes

CH2Cl2

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturathe reaction mixture was heated
2. 2
   Temperaturato reflux overnight
3. 3
   OtroThe layers were separated
4. 4
   Extracciónthe aqueous layer was extracted with CH2Cl2 (3×200 mL)
5. 5
   LavadoThe combined organic layers were washed with saturated NH4Cl solution (3×150 mL)
6. 6
   Secadodried over anhydrous MgSO4
7. 7
   Concentraciónconcentrated in vacuo

Procedimiento

Methanol (3.14 g, 98.22 mmol) was added drop-wise to a stirred suspension of LiBH4 (2.19 g, 101 mmol) in anhydrous CH2Cl2 (50 mL) under N2 atmosphere. After the addition of ethyl 6-bromo-2-methyl-2-p-tolyl-hexanoate (22 g, 67.28 mmol), the reaction mixture was heated to reflux overnight. The reaction mixture was cooled to 5° C. and hydrolized with ice (ca. 40 g) and saturated NH4Cl solution (150 mL) for 1 h. The layers were separated and the aqueous layer was extracted with CH2Cl2 (3×200 mL). The combined organic layers were washed with saturated NH4Cl solution (3×150 mL), dried over anhydrous MgSO4 and concentrated in vacuo to furnish 6-bromo-2-methyl-2-p-tolyl-hexan-1-ol (18.44 g, 96.2%) as an oil. 1H NMR (300 MHz, CDCl3/TMS): δ (ppm) 7.24-7.00 (m, 4H), 3.68-3.50 (m, 1H), 3.49-3.35 (m, 1H), 3.34-3.21 (t, J=6.9 Hz, 2H), 2.31 (s, 3H), 1.88-1.51 (m, 4H), 1.51-1.40 (m, 2H), 1.31 (s, 3H), 1.20-1.00 (m, 1H). 13C NMR (75 MHz, CDCl3/TMS): δ (ppm) 141.49, 135.74, 129.47, 126.63, 72.54, 43.03, 37.53, 33.69, 33.51, 22.66, 21.58, 20.98. HRMS (LSIMS, nba): Calcd. for C14H20Br (MH+—H2O): 267.0748, found: 267.0750.

Fuente