Tetrahydrofuran → (2S)-2-ethyl-2-hydroxy-3-methyl-but-3-enoic acid (1R,2S,5R)-5-methyl-2-(1-methyl-1-phenyl-ethyl)-cyclohexyl ester

반응식

[CH3:1][C@H:2]1[CH2:7][C@@H:6]([O:8][C:9](=[O:14])[C:10](=[O:13])[CH2:11][CH3:12])[C@H:5]([C:15]([CH3:23])([C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[CH3:16])[CH2:4][CH2:3]1.[C:24]([Mg]Br)(C)=[CH2:25].O1CCC[CH2:30]1>>[CH3:1][C@H:2]1[CH2:7][C@@H:6]([O:8][C:9](=[O:14])[C@@:10]([CH2:24][CH3:25])([OH:13])[C:11]([CH3:30])=[CH2:12])[C@H:5]([C:15]([CH3:23])([C:17]2[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=2)[CH3:16])[CH2:4][CH2:3]1

참가 물질

반응물 3

HCID 8028Tetrahydrofuran

HCID 110883962-oxo-butyric acid (1R,2S,5R)-5-methyl-2-(1-methyl-1-phenyl-ethyl)-cyclohexyl ester

HCID 178456138HCID 178456138, 화합물

생성물 1

HCID 11530561(2S)-2-ethyl-2-hydroxy-3-methyl-but-3-enoic acid (1R,2S,5R)-5-methyl-2-(1-methyl-1-phenyl-ethyl)-cyclohexyl ester

실험 절차

To a solution of 4.200 g of compound (17) as obtained from example 11 (13.27 mmol) in 168 mL tetrahydrofuran were added dropwise at −78° C. 39.8 mL isopropenylmagnesium bromide (19.91 mmol, 1.5 eq). After additional 50 min, the reaction mixture was quenched by addition of 110 mL saturated aqueous ammonium chloride solution, and was extracted twice with 110 mL ethyl acetate. The combined organic phases were washed with 110 mL brine, dried over 15 g sodium sulfate and were filtered. The filter cake was washed with 30 mL ethyl acetate. The organic phase was evaporated to dryness in a rotary evaporator (40° C., 8 mbar) yielding the title compound (4.790 g, 101% by weight, dr=93:7)as a yellow oil.