Dimethyl Sulfoxide → tert-butyl N-[(2S)-4-methyl-1-oxopentan-2-yl]carbamate

Temperature

0 °C

To a solution of the commercially available (Advanced Chem Tech) Boc-L-leucinol (0.78 g, 3.6 mmol) in anhydrous dichloromethane (17.5 ml) was added triethyl amine (2 ml, 14.36 mmol) and the mixture was cooled to 0° C. Dimethyl sulfoxide (17.5 ml) was added followed by sulfur trioxide pyridine complex (2.3 g, 14.36 mmol) and the reaction was stirred for two hours. TLC in 1:1 ethylacetate:hexanes confirmed the completion of the reaction. The reaction mixture was concentrated and the remaining residue diluted with ethylacetate. The ethylacetate layer was washed with 1M hydrochloric acid (2×75 ml) followed by saturated sodium bicarbonate solution (2×75 ml) and brine (75 ml). The organic layer was dried (sodium sulfate), filtered and concentrated to yield 775 mg of product.

1. customthe completion of the reaction
2. concentrationThe reaction mixture was concentrated
3. additionthe remaining residue diluted with ethylacetate
4. washThe ethylacetate layer was washed with 1M hydrochloric acid (2×75 ml)
5. dry with materialThe organic layer was dried (sodium sulfate)
6. filtrationfiltered
7. concentrationconcentrated

ORD record

ord-f533a0f1593842398b89d60dedda2461

Source dataset

uspto-grants-2007_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07244721B2