4-Cyanophenylboronic acid → 1,1-Dimethylethyl 3-(4-cyanophenyl)-1-azetidinecarboxylate

Participants

Reaction Steps

A modified procedure to that described in Org. Lett. 2008, 10, 3259 was performed as follows. To a 20-mL vial was added (4-cyanophenyl)boronic acid (1.01 g, 6.87 mmol), trans-2-aminocyclohexanol hydrochloride (32 mg, 0.21 mmol), nickel (II) iodide (66 mg, 0.21 mmol) and sodium hexamethyldisilazane (1.29 g, 7.06 mmol). The system was purged with nitrogen and charged with isopropyl alcohol (7 mL). The mixture was stirred at room temperature for 10 minutes then sonicated for 1 min. While stirring, tert-butyl 3-iodoazetidine-1-carboxylate (1.00 g, 3.53 mmol) was added and the syringe rinsed with isopropyl alcohol (2×500 μL). The suspension was stirred at 80° C. for 1 hour then concentrated under reduced pressure. The residue was purified by silica gel chromatography (hexanes to 25% ethyl acetate) to yield the title compound as a pale yellow oil which solidified upon standing (0.832 g, 46%). m/z (ES+) 203 (M-C4H8+H)+. 1H NMR (400 MHz, CDCl3): δ 7.65 (d with fine str., J=8.4 Hz, 2H), 7.43 (d with fine str., J=8.4 Hz, 2H), 4.37 (app t, J=8.8 Hz, 2H), 3.98-3.91 (m, 2H), 3.81-7.73 (m, 1H).

Provenance & Evidence