Sulfuric Acid → HCID 12127452, compound

d-Tartaric acid (23; 25 g, 0.17 mol), trifluoroethanol (200 ml) and H2SO4 (59 mL) were magnetically stirred and heated under reflux for 22 h. The solution was cooled to room temperature, partitioned between H2O and CH2C2. The H2O layer was extracted with CH2Cl2 (2×150 mL). The combined organic layers were washed with saturated aqueous NaHCO3, and brine, then filtered through a bed of Celite and evaporated in vacuo. The residue was dissolved in ethyl ether and filtered through a plug of silica. The silica was rinsed with ca. 600 mL. The ether was removed in vacuo and the residue was recrystallized from ether/hexane to yield 34 (17.3; 33%) as white crystals: mp 77-79° C.; 1H NMR (300 MHz, CDCl3) δ3.13 (two singlets, 2H), 4.6 (m, 6H).

1. temperatureheated
2. temperatureunder reflux for 22 h
3. custompartitioned between H2O and CH2C2
4. extractionThe H2O layer was extracted with CH2Cl2 (2×150 mL)
5. washThe combined organic layers were washed with saturated aqueous NaHCO3, and brine
6. filtrationfiltered through a bed of Celite
7. customevaporated in vacuo
8. dissolutionThe residue was dissolved in ethyl ether
9. filtrationfiltered through a plug of silica
10. washThe silica was rinsed with ca. 600 mL
11. customThe ether was removed in vacuo
12. customthe residue was recrystallized from ether/hexane

ORD record

ord-021761c945f841a5a9a4236a92485f1a

Source dataset

uspto-grants-2002_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06479477B1