反应详情

To a solution of 33.3 g. (0.15 mol) of 1-(toluene-p-sulphonyl)imidazole (H. A. Staab and K. Wendel, Ber. 93, (1960) 2902) in 300 ml. of anhydrous tetrahydrofuran and 150 ml. of anhydrous diethyl ether at a temperature of -40° to -50° C. under a nitrogen atmosphere were added drop-wise 91 ml. of a 20% solution of butyllithium in n-hexane (0.20 mol.) dissolved in 150 ml. of anhydrous diethyl ether. Upon completion of the addition, the mixture was kept at a temperature of -40° to -50° C. for one hour. Next and under identical conditions as to temperature 44.4 g. (0.17 mol) of 4-bromobenzophenone in 200 ml. of anhydrous tetrahydrofuran and 100 ml. of anhydrous diethyl ether were added drop-wise and the mixture was kept under the same conditions for another 3.5 hours. Cooling was stopped and the mixture was allowed to reach ambient temperature in 1/2 hour. It was then poured out into about 250 ml. of a sodium chloride solution. The aqueous layer was separated and discarded, the organic solvents layer was washed with 100 ml. of a sodium chloride solution, dried and concentrated. The residual oil was brought to crystallisation by addition of a very small amount of diethyl ether. Purification was brought about by crystallisation from warm ethanol to which some acetone was added. Melting point of the product was 138°-140° C.

1. additionUpon completion of the addition
2. waitthe mixture was kept under the same conditions for another 3.5 hours
3. temperatureCooling
4. waitto reach ambient temperature in 1/2 hour
5. additionIt was then poured out into about 250 ml
6. customThe aqueous layer was separated
7. washthe organic solvents layer was washed with 100 ml
8. dry with materialof a sodium chloride solution, dried
9. concentrationconcentrated
10. customThe residual oil was brought to crystallisation by addition of a very small amount of diethyl ether
11. customPurification
12. customwas brought about by crystallisation
13. temperaturefrom warm ethanol to which some acetone
14. additionwas added
15. customwas 138°-140° C.