Isopropanol → tert-butyl[(1S,2R)-2-(4-ethylphenyl)-2-hydroxy-1-methylethyl]carbamate

The procedure described by J. Yin et al., J. Org. Chem. 2006, 71, 840-843) was used. A mixture of tert-butyl [(1S)-2-(4-ethylphenyl)-1-methyl-2-oxoethyl]carbamate (555 mg, 2 mmol), Al(iPr)3 (81 mg, 0.4 mmol), 2-propanol (1.32 g, 22 mmol), and toluene (2.6 ml, 1.3 ml/mmol) was heated in a sealed vial at 50° C. overnight. Then the reaction mixture was cooled to r.t., quenched with aqueous HCl (1 N, 10 ml), and diluted with ethyl acetate (10 ml). The layers were separated, the organic layer was washed with water (80 ml), dried with Na2SO4, and concentrated. Trituration with n-heptane (30 ml) afforded the subtitle compound as colourless precipitate, 137 mg. n-Heptane solution was concentrated under reduced pressure, and the residue purified by flash chromatography in silica gel to give the second crop of the subtitle compound, 318 mg. Overall yield 455 mg (81%).

1. temperatureThen the reaction mixture was cooled to r.t.
2. customquenched with aqueous HCl (1 N, 10 ml)
3. additiondiluted with ethyl acetate (10 ml)
4. customThe layers were separated
5. washthe organic layer was washed with water (80 ml)
6. dry with materialdried with Na2SO4
7. concentrationconcentrated

ORD-Eintrag

ord-1f6ee88b4f7d472a858cde3639a923c8

Quelldatensatz

uspto-grants-2012_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08143290B2