(+)-Pantolactone → (S)-3,3-Dimethylbutane-1,2,4-triol

Temperatur

0 °C

To a 0° C. solution of 5.01 g (38.5 mmol) of (S)-(+)-pantolactone in 150 mL of methanol was added 3.72 g (98.5 mmol) of sodium borohydride carefully. After gas evolution had subsided, the ice-bath was removed and the reaction mixture was closely monitored, cooling again to 0° C. with an ice-water bath as needed when gas evolution became vigorous. The ice-water bath was removed and the reaction mixture was stirred at room temperature for 4 h. Dowex 50Wx4-400 (H+) resin was added to the solution until the reaction mixture was neutral. The resin was filtered off and the filtrate was concentrated under reduced pressure. The oil was diluted and concentrated with portions of methanol and then toluene. The remaining clear oil was dried under high vacuum to afford 5.16 g (>99%) of (2S)-3,3-dimethyl-1,2,4-butanetriol. 1H-NMR (300 MHz, CDCl3): δ 3.82–3.49 (m, 5H), 3.11 (d, J=4 Hz, 1H), 2.62 (m, 1H), 2.42 (m, 1H), 0.98 (d, J=6 Hz, 6H).

1. customthe ice-bath was removed
2. customThe ice-water bath was removed
3. additionDowex 50Wx4-400 (H+) resin was added to the solution until the reaction mixture
4. filtrationThe resin was filtered off
5. concentrationthe filtrate was concentrated under reduced pressure
6. additionThe oil was diluted
7. concentrationconcentrated with portions of methanol
8. customThe remaining clear oil was dried under high vacuum

ORD-Eintrag

ord-6b92827c9cd94eac8704af04178f4c8e

Quelldatensatz

uspto-grants-2007_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07288541B2