Hydrogen Peroxide → HCID 21963873, compound

1-Methyl-3-(2-methylbut-3-ene-1-sulphonyl)benzene (444 mg, 1.96 mmol) was dissolved in tetrahydrofuran (5 ml) and cooled to −78° C. n-Butyllithium (1.6M in hexanes, 1.96 mmol) was added. The reaction was treated with methyl iodide (130 μL, 2.16 mmol) and allowed to warm to room temperature. The mixture was quenched with saturated aqueous ammonium chloride solution and extracted with ethyl acetate. The combined organic layers were dried (MgSO4) and concentrated in vacuo to give a 1:1 mixture of dimethyl diastereoisomers containing approximately 28% monomethyl starting material. This crude mixture (265 mg, 1.12 mmol) was dissolved in tetrahydrofuran (3 ml) at 0° C. and treated with borane-tetrahydrofuran complex (1.0M in tetrahydrofuran, 4.5 ml, 4.5 mmol) then allowed to warm to room temperature and stirred for 6 hours. The reaction was treated cautiously with pre-mixed hydrogen peroxide 35% w/w (5 ml) and water (5 ml) and stirred for 18 hours. The reaction mixture was extracted with ethyl acetate and the combined organic layers were concentrated in vacuo to give a clear oil which was purified by preparative thin layer chromatography, eluting with 25% ethyl acetate/i-hexane to give a 1:1 mixture of diastereoisomers that was used in the next step.

1. additionwas added
2. customThe mixture was quenched with saturated aqueous ammonium chloride solution
3. extractionextracted with ethyl acetate
4. dry with materialThe combined organic layers were dried (MgSO4)
5. concentrationconcentrated in vacuo
6. customto give
7. additiona 1:1 mixture of dimethyl diastereoisomers
8. additioncontaining approximately 28% monomethyl starting material
9. temperatureto warm to room temperature
10. stirringstirred for 18 hours
11. extractionThe reaction mixture was extracted with ethyl acetate
12. concentrationthe combined organic layers were concentrated in vacuo
13. customto give a clear oil which
14. customwas purified by preparative thin layer chromatography
15. washeluting with 25% ethyl acetate/i-hexane
16. customto give
17. additiona 1:1 mixture of diastereoisomers that

ORD record

ord-101ed6fbe2884d0e9eb3e6cce6731c7b

Source dataset

uspto-grants-2006_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07101892B2