2-Methoxycyclohexanone → HCID 6951549, compound

Kinetic resolution of racemic 2-methoxycyclohexanone was carried out (see formula (16) below) That is, a reaction was carried out in accordance with the procedures of Example 13 using the (S,SS)-ruthenium hydride complex (1.5 mg; 0.00125 mmol) synthesized in Example 2 and using 2-methoxycyclohexanone (320 mg; 2.5 mmol) (made by Tokyo Kasei Kogyo Co., Ltd. )as the substrate and 2-propanol (2.5 mL) as the solvent. However, the hydrogen pressure was set to 8 atmosphere, the reaction temperature was set to 25° C., and the reaction time was set to 1 hours. As a result, (R)-2-methoxycyclohexanone was obtained at isolation yield of 42% (134 mg; 1.05 mmol), (1R, 2S)-2- methoxycyclohexanol was obtained at isolation yield of 50% (164 mg; 1.25 mmol and enantiomeric excess of 91%). GC (column: Chirasil-DEX CB; column temperature:90° C.; injection and detection temperature: 200° C.; helium pressure: 25 kPa; tR of (1R,2S)-2-methoxycyclohexanol: 37.6 minutes(50.8%); tR of 1S, 2S alcohol: 36.5 minutes (2.5%); tR of 2-methoxycyclohexanone:27.0 minutes (46.7%)). enantiomeric excess of (R)-2-methoxycyclohexanone:94% : HPLC (column: CHIRALCEL OB-H; solvent: 200:1 hexane/2-propanol; temperature: 30° C.; UV wavelength: 290 nm; flow rate: 1.0 ml/minute; tR of (R)-2-methoxycyclohexanone: 20.9 minutes (97.2%); tR of Sketone: 17.0 minutes (2.8%). specific rotation of ketone: [α]29D+98.8° (c:2.61; CH2Cl2); absolute structure: R; literature value: [α]22D−112.4° (c:2.08;CH2Cl2),>99%ee(S). specific rotation of alcohol: [α]29D+14.9° (c:1.026; CH2Cl2); absolute structure: 1R, 2S: the absolute structure was determined by HPLC analysis of the product of oxidation of (1R, 2S)-2-methoxycyclohexanol.

1. customsynthesized in Example 2
2. customwas set to 25° C.

ORD record

ord-1ba2c345f1a5402eaa5b475325c37e8f

Source dataset

uspto-grants-2004_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06720439B1