Methyl 2-formylbenzoate → HCID 67733921, compound

Participants

Reaction Steps

To a solution of 5.48 g (17.2 mmol) of trans-4-amino-3,4-dihydro-2,2-dimethyl-6-iodo-2H-1-benzopyran-3-ol as prepared in Example 1 in methanol (34 mL) containing 3.38 g (20.6 mmol) of 2-carbomethoxybenzaldehyde was added 68.7 mL (34.4 mmol) of 0.5 M zinc chloride-modified sodium cyanoborohydride in methanol, prepared according to the method of Kim et. al. L. Org. Chem. 50 (11), 1927 (1985). The reaction mixture was refluxed for 3 h, cooled to room temperature and quenched with water (375 mL). The reaction mixture was extracted into 20% THF/CH2Cl2, and the extracts were dried over MgSO4. Purification was achieved by flash chromatography (CH2Cl2 :MeOH:NH4OH (94.75: 3.5: 1.75) to give 7.07 g of the title compound as a white solid. An analytical sample, mp 224°-228° C., was obtained by additional flash chromatography using (25% Et 2 O-CH2Cl2): 1H-NMR (DMSO-d6 ; 300 MHz) δ7.79 (d, 1 H), 7.53-7.68 (m, 3 H), 7.46 (dd, 1 H), 7.02 (s, 1 H), 6.67 (d, 1 H), 5.75 (d, 1 H), 5.1 (bs, 1 H), 4.5 (br d, 1 H), 4.1 (br, d 1 H), 3.89 (br, 1 H), 1.45 (s, 3 H), and 1.22 ppm (s, 3 H); mass spectrum (CI), m/e 436, 435, 417, 402. Anal. Calcd. for C19H18INO3. 1 H2O: C, 51.36; H, 4.31; N, 3.15 Found: C, 51.62; H, 4.04; N, 2.95.

Provenance & Evidence