Chlorotrimethylsilane → HCID 22150552, compound

A mixture of 2.7 ml of tetramethylethylenediamine and 2.0 g of zinc-copper couple in 30 ml of tetrahydrofuran was stirred at room temperature, and a solution of 11.3 ml of chlorotrimethylsilane and 950 mg of 6-chlorobicyclo[4.2.0]oct-2-en-7 one, prepared as shown in Preparation 7, in 30 ml of tetrahydrofuran added dropwise. The mixture was stirred overnight at room temperature, then the precipitate filtered off, washed with ether and the combined filtrates evaporated under reduced pressure. The residue was treated with a mixture of diethylether and hexane, the precipitate filtered off and solvent removed from the filtrate under reduced pressure. The residue was dissolved in 10 ml of tetrahydrofuran, cooled to -78° C., 4 ml of 1.5M methyllithium added, stirred at -78° C. for 10 minutes, then at -30° C. for 10 minutes, recooled to -78° C. and a mixture of 5.1 g of methyl iodide and 2.1 ml of hexamethylphosphoramide added. The temperature was allowed to rise to room temperature while stirring. The mixture was poured into water, extracted with ether and the solvent removed from the extract carefully under moderately reduced pressure. The residue was chromatographed on silica gel, eluting with 10% ether in pentane, giving 400 mg of 6-methylbicyclo[4.2.0]oct-2-en-7-one, the compound of formula (8) where Y is hydrogen.

1. additionadded dropwise
2. stirringThe mixture was stirred overnight at room temperature
3. filtrationthe precipitate filtered off
4. washwashed with ether
5. customthe combined filtrates evaporated under reduced pressure
6. additionThe residue was treated with a mixture of diethylether and hexane
7. filtrationthe precipitate filtered off
8. customsolvent removed from the filtrate under reduced pressure
9. dissolutionThe residue was dissolved in 10 ml of tetrahydrofuran
10. temperaturecooled to -78° C.
11. addition4 ml of 1.5M methyllithium added
12. stirringstirred at -78° C. for 10 minutes
13. customrecooled to -78° C.
14. additiona mixture of 5.1 g of methyl iodide and 2.1 ml of hexamethylphosphoramide
15. additionadded
16. customto rise to room temperature
17. stirringwhile stirring
18. additionThe mixture was poured into water
19. extractionextracted with ether
20. customthe solvent removed from the
21. extractionextract carefully under moderately reduced pressure
22. customThe residue was chromatographed on silica gel
23. washeluting with 10% ether in pentane

ORD record

ord-eab7ac2e52e34b5dabc8beb9a5e56b2b

Source dataset

uspto-grants-1991_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04983627