Sulfuric Acid → HCID 58736783, compound

Temperature

0 °C

A solution of sodium nitrite (2.26 g, 32.7 mmol) in water (6 ml) was added drop-wise at 0° C. over 4 hours to a stirred mixture of (s)-α-aminocyclohexanepropionic acid (5 g, 29.2 mmol), potassium bromide (11.40 g, 95.8 mmol) and concentrated sulphuric acid (3.3 ml) in water (35 ml). The mixture was stirred for 5 hours at 0° C. then at ambient temperature for 16 hours. The product was extracted into diethyl ether (4×50 ml) then the combined ethereal layers were washed with saturated aqueous sodium chloride solution (2×50 ml), dried (MgSO4) and the solvent removed in vacuo. The residue was purified by chromatography over silica gel eluting with a gradient of methanol:dichloromethane 1:50→1:20. Appropriate fractions were combined and the solvents removed in vacuo to leave (S)-α-bromocyclohexanepropionic acid as a pale yellow oil (3.64 g, 53%). TLC (single spot, Rf=0.45, 10% methanol in dichloromethane), HPLC-MS (single main peak with Rt=8.85 mins, 234.1/236.1 [M+H]+).

1. waitat ambient temperature for 16 hours
2. extractionThe product was extracted into diethyl ether (4×50 ml)
3. washthe combined ethereal layers were washed with saturated aqueous sodium chloride solution (2×50 ml)
4. dry with materialdried (MgSO4)
5. customthe solvent removed in vacuo
6. customThe residue was purified by chromatography over silica gel eluting with a gradient of methanol:dichloromethane 1:50→1:20
7. customthe solvents removed in vacuo

ORD record

ord-43d9487a34d849d5876367207486e2db

Source dataset

uspto-grants-2006_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07132449B2