Phosphorus oxychloride → Methyl 2,6-dichlorobenzoxazole-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of the product from Step A (2.00 g, 8.20 mmol), POCl3 (1.26 g, 8.21 mmol), and PCl5 (1.71 g, 8.21 mmol) was heated to 125° C. for 2.5 hours. The reaction mixture was dried under high vacuum for 24 hours to afford methyl 2,6-dichlorobenzoxazole-4-carboxylate (2.00 g, 99%) as a brown solid: 1H NMR (300 MHz, CDCl3) δ 8.04 (d, J=2.0 Hz, 1H), 7.72 (d, J=2.0 Hz, 1H), 4.04 (s, 3H); MS (ESI+) m/z 247 (M+H).

Provenance & Evidence