反应详情

温度

-20 °C

A solution of 0.902 ml of dimethylformamide in 20 ml of acetonitrile was placed at -20° C. while gassing with argon in a sulphonation flask fitted with a mechanical stirrer, serum cap, thermometer and dropping funnel and treated within 2 minutes with 0.338 ml of oxalyl chloride. After completion of the addition, the mixture was stirred at -20° C. for a further 20 minutes and then 1.0 g of trans-4-(trans-4-pentylcyclohexyl)cyclohexanecarboxylic acid was introduced into the resulting white suspension via a solid substance addition tube. The mixture was subsequently stirred at -20° C. for 30 minutes and then treated dropwise at -20° C. within 10 minutes with a solution of 1.97 g of trans-4-(p-propylphenyl)cyclohexanol and 0.9 ml of pyridine in 20 ml of acetonitrile. The mixture was stirred for a further 15 hours while slowly warming to room temperature, then poured into 200 ml of cold 2N sodium carbonate solution and extracted three times with 200 ml of methylene chloride each time. The organic phases were washed once with 100 ml of 2N sodium carbonate solution and twice with 200 ml of water each time, dried over magnesium sulphate and concentrated. Low-pressure chromatography (0.5 bar) of the residue (2.6 g) on 140 g of silica gel using toluene/hexane (volume ratio 1:1) gave 757 mg (44%) of trans-4-(trans-4-pentylcyclohexyl)cyclohexanecarboxylic acid trans-4-(p-propylphenyl)cyclohexyl ester as colourless crystals. A single recrystallization from acetone yielded analytically-pure product of m.p. (C-S) 63.3° C., phase transition S-N 241.5° C., cl.p. (N-I) 285.5° C.

1. customwas placed at -20° C.
2. customwhile gassing with argon in a sulphonation flask
3. customfitted with a mechanical stirrer
4. customserum cap
5. additionAfter completion of the addition
6. stirringThe mixture was subsequently stirred at -20° C. for 30 minutes
7. stirringThe mixture was stirred for a further 15 hours
8. temperaturewhile slowly warming to room temperature
9. extractionextracted three times with 200 ml of methylene chloride each time
10. washThe organic phases were washed once with 100 ml of 2N sodium carbonate solution and twice with 200 ml of water each time
11. dry with materialdried over magnesium sulphate
12. concentrationconcentrated