反应详情

Borane-dimethylsulfide (34 mL, 0.34 mmol) was added to a solution of 2-iodo-3-nitrobenzoic acid (43) [P. J. Culhane, Org. Synth. Coll. Vol 1, 1967, 125-127] (82.3 g, 0.28 mol) and trimethyl borate (64 mL, 0.56 mol) in dry THF (400 mL) under nitrogen, and the mixture stirred at reflux for 90 min. The solution was cooled, MeOH then H2O were added, and the mixture was evaporated. Aq NaCl was added to the residue and the mixture was extracted with EtOAc (×3). The extracts were washed with aq NaCl, dried (Na2SO4), and evaporated to give crude 2-iodo-3-nitrobenzyl alcohol (44) as a yellow-orange solid suitable for use in the next step. A sample was filtered through a short column of silica eluting with CH2Cl2 and recrystallized from PhH as pale yellow needles, mp 91-91.5° C. 1H NMR (CDCl3) δ 7.72 (dd, J=7.7, 1.1 Hz, 1 H, H-4 or 6), 7.59 (dd, J=8.1, 1.5 Hz, 1 H, H-4 or 6), 7.50 (t, J=7.8 Hz, 1 H, H-5), 4.78 (s, 2 H, CH2), 2.14 (br s, 1 H, OH). Anal. Calculated for C7H6INO3 : C, 30.1; H, 2.2; N, 5.0. Found: C, 30.4; H, 2.1; N, 4.9%.

1. temperatureat reflux for 90 min
2. temperatureThe solution was cooled
3. customthe mixture was evaporated
4. additionAq NaCl was added to the residue
5. extractionthe mixture was extracted with EtOAc (×3)
6. washThe extracts were washed with aq NaCl
7. dry with materialdried (Na2SO4)
8. customevaporated