تفاعل #1737110

معادلة التفاعل

2-bromo-1,1-dimethoxyethane

Cyclohexanol

sodium hydride

→

2-cyclohexyloxy-1,1-dimethoxyethane

المذيبات

DMPU

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGStirring
2. 2
   workup.WAITwas continued for 18 hours at ambient temperature
3. 3
   استخلاصThe aqueous mixture was extracted with ether (4×100 ml)
4. 4
   غسيلThe combined extracts were washed successively with water (3×100 ml) and saturated brine (100 ml)
5. 5
   تجفيفdried (MgSO4)
6. 6
   أخرىevaporated
7. 7
   غسيلFlash chromatography of the residue, eluting successively with hexane, 5% v/v ethyl acetate hexane and 10% v/v ethyl acetate/hexane

الإجراء التجريبي

Cyclohexanol (11.00 g) was added slowly over 2 hours to a stirred suspension of sodium hydride (4.80 g, 50% w/w dispersion in oil) in dry DMPU (100 ml) at 50° C. under argon. The mixture was stirred for an additional 30 minutes, then cooled to 5° C. and treated with 2-bromo-1,1-dimethoxyethane (16.9 g). Stirring was continued for 18 hours at ambient temperature. The mixture was then poured into ice-water (250 ml). The aqueous mixture was extracted with ether (4×100 ml). The combined extracts were washed successively with water (3×100 ml) and saturated brine (100 ml), then dried (MgSO4) and evaporated. Flash chromatography of the residue, eluting successively with hexane, 5% v/v ethyl acetate hexane and 10% v/v ethyl acetate/hexane, gave 2-cyclohexyloxy-1,1-dimethoxyethane as an oil (A) (7.32 g). This was used without further purification. [A sample was distilled under vacuum (bulb to bulb transfer); NMR: 1.29 (5H,m), 1.55 (1H,m), 1.76 (2H,m), 1.92 (2H,m), 3.27 (1H,m), 3.40 (6H,s), 3.50 (2H,d J=5 Hz), 4.48 (1H,t J=5 Hz).]

المصدر