Water → (S)-a-Hydroxy-cyclobutanepropanoic acid

A suspension of 33.66 g (0.3 mol) of potassium t-butoxide in 50 mL of THF was treated with 5.40 mL (0.3 mol) of H2O. The resulting mixture was treated with a solution of 11.48 g (0.061 mol) of N-methyl-N-methoxy 2-(S)-hydroxy-3-cyclobutyl propanamide (from Step C) in 20 mL of THF and stirred at rt for 20 h. The mixture was concentrated and the residue was partitioned between 300 mL of ether and 200 mL of H2O and the layers were separated. The pH of the aqueous layer was adjusted to 2 with concentrated HCl and extracted with 300 mL of EtOAc. The extract was washed with 100 mL of sat'd NaCl, dried over MgSO4 and concentrated to afford 7.50 g (85%) of the title compound: 1H NMR (500 MHz) δ 1.66-1.76 (m, 2H), 1.78-1.98 (4H), 2.06-2.16 (m, 2H), 2.51-2.61 (m, 1H), 4.20 (dd, J=8.0, 4.0, 1H).

1. concentrationThe mixture was concentrated
2. customthe residue was partitioned between 300 mL of ether and 200 mL of H2O
3. customthe layers were separated
4. extractionextracted with 300 mL of EtOAc
5. washThe extract was washed with 100 mL of sat'd NaCl
6. dry with materialdried over MgSO4
7. concentrationconcentrated

ORD record

ord-1109b15d67a24da1a58a8197306929e4

Source dataset

uspto-grants-2002_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06498161B1