2-Cyclohexen-1-one → 3-Butylcyclohexanone

Temperatur

-78 °C

A THF (5 mL) suspension of CuBr.Me2S (26.3 mg, 0.128 mmol) was treated with 1.0 equiv of n-BuLi at -78° C. under an argon atmosphere. The mixture was allowed to warm up slightly with the formation of a bright yellow solid. The mixture was again cooled to -78° C. and treated with Li(CHIRAMT) formed from compound 4 (85.8 mg, 0.261 mmol) and n-BuLi (1.0 equiv). The yellow slurry was stirred with gradual warming until a homogeneous burgundy solution was obtained. In the case of R=Me, a homogeneous mixture was not obtained even after prolonged stirring at room temperature, and it was evident that unreacted (CuMe)n was still present. The solution was cooled to -78° C. and THF (8 mL each) solutions of n-BuMgCl (25.0 equiv) and cyclohexenone (0.3068 g, 3.19 mmol) were added dropwise and simultaneously over a 5 min period. The resulting reaction mixture was stirred for an additional 10 min at -78° C., quenched with saturated aqueous NH4Cl solution (7 mL), and worked up as described in the previous section. Pure 3-butylcyclohexanone (0.4617 g, 94%) was obtained as checked by glc.

1. temperaturewith gradual warming until a homogeneous burgundy solution
2. customwas obtained
3. customIn the case of R=Me, a homogeneous mixture was not obtained even
4. stirringafter prolonged stirring at room temperature
5. customThe resulting reaction mixture
6. stirringwas stirred for an additional 10 min at -78° C.
7. customquenched with saturated aqueous NH4Cl solution (7 mL)

ORD-Eintrag

ord-5305ffc08cde4e59b1a355accdbad04c

Quelldatensatz

uspto-grants-1992_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05162586