Boron trifluoride etherate → Methyl 4-(1-aminocyclopropyl)benzoate

Participants

Reaction Steps

Methyl 4-cyanobenzoate (2.6 kg, 16.1 mol) was dissolved in 40 L of toluene at −25° C. and Ti(Oi-Pr)4 (4.73 L, 16.1 mol) was added over 5 min, followed by EtMgBr (10.5 L of a 3.07M solution in THF, 32.3 mol) over 2 hr. After aging for 30 min, BF3.OEt2 (4.1 L, 32 mol) was added over 40 min and the mixture was aged for another 40 min. The reaction was quenched by the addition of 40 L of 3N HCl. The layers were separated and the aqueous layer was washed with 13 L toluene. The aqueous layer was then extracted with 2-MeTHF (2×26 L and 2×13 L). The combined 2-MeTHF layers were washed with 3N NaOH and the pH of the NaOH layer adjusted to 9 before separation of the layers. The organic layer was washed with 13 L of brine. Yield=43%. 1H NMR (500 MHz, CDCl3): δ 8.00 (d, 2H), 7.35 (d, 2H), 3.95 (s, 3H), 1.25 (t, 2H), 1.10 (t, 2H).

Provenance & Evidence