反应详情

To a solution of methyl 4-[4′-(hydroxymethyl)-2′-methoxy-5′-nitrophenoxy]butanoate (6) (750 mg, 2.52 mmol) in anhydrous THF (10 cm3) was added PBr3 (0.24 cm3, 2.52 mmol). The resulting deep yellow solution was refluxed for 3 hours, after which time no visible changes had occurred. The reaction mixture was cooled then poured onto ice. The resulting aqueous solution was extracted with ether (3×30 cm3). The combined organic extracts were washed with 5% NaHCO3 solution (2×30 cm3) and water (2×30 cm3) before being dried (MgSO4) and concentrated in vacuo. The desired compound 7 was furnished as a yellow oil. The oil was then purified via column chromatography (SiO2, hexane:EtOAc, 2:1 v/v) thus providing 7 as a yellow powder (580 mg, 64%). m.p. 68-70° C. Found C, 43.2; H, 4.5; N, 4.0; Br, 21.9; C13H16NO6Br requires C, 43.1; H, 4.4; N, 3.9; Br, 22.1%; Rf 0.63 (SiO2, hexane:EtOAc 2:1 v/v); νmax (KBr disc)/cm−1 3000-2800 (m), 1720 (s), 1610, 1580, 1530, 1280, 1220; δH (200 MHz, CDCl3) 2.20 (2H, q, J=6.7 Hz, CH2), 2.56 (2H, t, J=6.7 Hz, CH2), 3.70 (3H, s, OCH3), 3.97 (3H, s, OCH3), 4.13 (2H, t, J=6.7 Hz, CH2), 4.86 (2H, s, CH2), 6.92 (1H, s, H-3′), 7.67 (1H, s, H-6′) ppm; δC (100 MHz, CDCl3) 24.1 (CH2), 30.1 (CH2), 51.6 (OCH3), 56.4 (OCH3), 68.0 (CH2), 68.3 (CH2), 109.7 (CH), 113.8 (CH), 127.3, 140.0, 148.1, 153.5, 173.2 (COOCH3) ppm; m/z (FAB) 362 [(MH+), 100%].

1. temperatureThe resulting deep yellow solution was refluxed for 3 hours
2. temperatureThe reaction mixture was cooled
3. additionthen poured onto ice
4. extractionThe resulting aqueous solution was extracted with ether (3×30 cm3)
5. washThe combined organic extracts were washed with 5% NaHCO3 solution (2×30 cm3) and water (2×30 cm3)
6. dry with materialbefore being dried (MgSO4)
7. concentrationconcentrated in vacuo