Tetrahydrothiophene → Aniline

Temperature

-78 °C

To a vigorously stirred solution of 10.0 grams (0.11 mole) of aniline in 200 ml. of methylene chloride cooled to -78° C. under nitrogen were added by means of a jacketed constant pressure additional funnel 11.7 grams (0.11 mole) of tert.-butyl hypochlorite also cooled to -78° C. This solution was stirred for 10 minutes. The funnel was rinsed with a few ml. of cold methylene chloride and 44 ml. (ca. 5 equivalents) of tetrahydrothiophene was cooled to -78° C., added dropwise to the reaction mixture, and stirred for 3 hours. In 50 ml. of methanol, 7.0 grams (0.13 mole, 1.2 equivalents) of sodium methoxide were placed in the funnel, cooled, and added quickly to the reaction mixture. The dry-ice/acetone cooling bath was removed and the solution stirred for 2 hours. The reaction was quenched by the addition of 100 ml. of water, the heterogeneous mixture separated, the aqueous layer was extracted two times with 100-ml. portions of methylene chloride. The combined organic layers were washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate, and filtered. The solvent was removed in vacuo to produce a dark red oil. Fractional distillation of the oil gave 5.03 grams (0.054 mole) of aniline and 6.11 grams (0.034 mole) of 2-(2-tetrahydrothienyl)aniline for a 31% yield based on starting material and a 64% yield based on unrecovered starting material: b.p. 130°-134° C. (0.19 mm), ND26.8 1.6258, IR (neat) 2.92, 3.36, 6.12, 6.70, and 13.40μ, NMR (CCl4)T 7.82 (4H, m), 6.99 (2H, m) 6.06 (2H, s), 5.52 (2H, t), 3.20 (4H, m).

1. washThe funnel was rinsed with a few ml
2. additionadded dropwise to the reaction mixture
3. stirringstirred for 3 hours
4. temperaturecooled
5. additionadded quickly to the reaction mixture
6. customThe dry-ice/acetone cooling bath was removed
7. stirringthe solution stirred for 2 hours
8. customThe reaction was quenched by the addition of 100 ml
9. customof water, the heterogeneous mixture separated
10. extractionthe aqueous layer was extracted two times with 100-ml
11. washThe combined organic layers were washed with saturated sodium chloride solution
12. dry with materialdried over anhydrous sodium sulfate
13. filtrationfiltered
14. customThe solvent was removed in vacuo
15. customto produce a dark red oil
16. distillationFractional distillation of the oil

ORD record

ord-36e0a0b56d6c4d13b57a15d37c984496

Source dataset

uspto-grants-1976_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US03985756