反应详情

温度

26 °C

Under a static nitrogen atmosphere at 0° C., a solution of n-butyllithium (4.03 g, 0.063 mol) in hexane was added to a solution of tetramethylethylenediamine (1.86 g, 0.016 mol) in 30 ml. of anhydrous cyclohexane with constant stirring. While maintaining the temperature of the reaction at 0° C., a solution of N-benzylaniline (5.5 g, 0.03 mol) in 30 ml. of anhydrous cyclohexane was added to the reaction mixture to produce a suspension containing a dilithio compound. The suspension was stirred for 2 hours at 26° C. and then cooled to 0° C. A solution of 4-chlorophenylphosphonic dichloride (7.35 g, 0.032 mol) in 30 ml. of anhydrous cyclohexane was rapidly added to the suspension. After stirring for 15 minutes at 0° C., the resulting mixture was stirred for 2 hours at 26° C. The reaction mixture was cooled to 0° C., then quenched with the rapid addition of 6 ml. of acetic acid. After stirring for 15 minutes, the cyclohexane was removed on a rotary evaporator and the resulting residue was partitioned between methylene chloride and water. The layers were separated and the methylene chloride layer was washed with 5% hydrochloric acid, then water, dried with sodium sulfate and concentrated in vacuo to yield a blue oil. The blue oil was separated on a silica gel column using first methylene chloride then a 3:1 mixture of methylene chloride:ethyl acetate as the eluant. Fractions containing the benzazaphosphole were combined and concentrated in vacuo to yield a crude product. The crude product was slurried in anhydrous diethyl ether to yield 1-(4-chlorophenyl)-2-phenyl-2,3-dihydro-1H-2,1-benzazaphosphole-1-oxide (1.0 g, 5% yield) as a white crystalline solid having a melting point of 180°-182° C. and the following analysis:

1. temperatureWhile maintaining
2. customthe temperature of the reaction at 0° C.
3. customto produce a suspension
4. temperaturecooled to 0° C
5. stirringAfter stirring for 15 minutes at 0° C.
6. stirringthe resulting mixture was stirred for 2 hours at 26° C
7. temperatureThe reaction mixture was cooled to 0° C.
8. customquenched with the rapid addition of 6 ml
9. stirringAfter stirring for 15 minutes
10. customthe cyclohexane was removed on a rotary evaporator
11. customthe resulting residue was partitioned between methylene chloride and water
12. customThe layers were separated
13. washthe methylene chloride layer was washed with 5% hydrochloric acid
14. dry with materialwater, dried with sodium sulfate
15. concentrationconcentrated in vacuo
16. customto yield a blue oil
17. customThe blue oil was separated on a silica gel column
18. additiona 3:1 mixture of methylene chloride
19. additionFractions containing the benzazaphosphole
20. concentrationconcentrated in vacuo
21. customto yield a crude product