3-Oxo-azetidine-1-carboxylic acid tert-butyl ester → Tert-butyl 3-(3-hydroxy-3-methyl-azetidin-1-YL)azetidine-1-carboxylate

Participants

Reaction Steps

A 10 mL round-bottomed flask was charged with a solution of 3-oxoazetidine-1-carboxylic acid tert-butyl ester (0.21 g, 1.23 mmol), 3-methylazetidin-3-ol (0.13 g, 1.48 mmol) and 4 Å molecular sieves (1.2 g) in DCE (5 mL). The reaction mixture was stirred for 3 h at room temperature. Sodium triacetoxyborohydride (0.52 g, 2.47 mmol) was added and the reaction mixture was stirred for 18 h at room temperature. The suspension was filtered through Celite and the solution was concentrated in vacuo. The residue was purified by flash chromatography (Si—PPC, EtOAc:cyclohexane, 0:100 to 100:0) to give 3-Hydroxy-3-methyl-[1,3′]biazetidinyl-1′-carboxylic acid tert-butyl ester as a colourless oil (0.09 g, 30%). 1H NMR (300 MHz, CDCl3): δ 3.93 (dd, J=9.2, 7.2 Hz, 2 H), 3.82-3.70 (m, 2 H), 3.50-3.40 (m, 1 H), 3.32 (d, J=8.1 Hz, 2 H), 3.21 (d, J=8.1 Hz, 2 H), 1.51 (s, 3 H), 1.43 (s, 9 H).

Provenance & Evidence