Triethyl phosphite → Diethyl (4-methoxy-2-nitrobenzyl)phosphonate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 1-(bromomethyl)-4-methoxy-2-nitrobenzene (14.2 g; 57.71 mmol; 1 eq) and triethyl phosphite (9.49 mL; 54.82 mmol; 0.95 eq) is heated at 120° C. for 1 h. TLC analysis using cyclohexane/EtOAc [1/1] as eluent showed that the reaction is complete. The reaction mixture is cooled down to room temperature. The crude is purified by flash chromatography to afford 16.2 g (93%) of an orange oil. Storage at −25° C. allows the product to crystallize. It is then washed with petroleum ether and filtered to afford 14.4 g (82%) of the title compound. 1H NMR (DMSO-d6) δ 7.50 (d, J=3.0 Hz, 1H), 7.45 (dd, J=9.0, 2.0 Hz, 1H), 7.28 (dd, J=9.0, 2.0 Hz, 1H), 3.98-3.89 (m, 4H), 3.84 (s, 3H), 3.64 (s, 1H), 3.57 (s, 1H), 1.14 (t, J=7.0 Hz, 6H). HPLC (max plot) 99%; Rt 3.29 min. LC/MS: (ES+): 304.3, (ES−): 302.2.

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