Boron Trichloride → HCID 86612905, compound

Temperature

-78 °C

To a solution of the compound 6.5 (0.71 g, 1.1 mmol) in 30 mL of anhydrous CH2Cl2 at −78° C. was added boron trichloride (1M solution in CH2Cl2, 11 mL, 11 mmol) dropwise. The mixture was stirred at −78° C. for 2.5 h, then at −30° C. to −20° C. for 3 hr. The reaction was quenched by addition of methanolic/CH2Cl2 (1:1) (5 mL) and the resulting mixture stirred at −15° C. for 30 min., then neutralized with aqueous ammonia at 0° C. and stirred at room temperature for 15 min. The solid was filtered and washed with CH2Cl2/MeOH (1/1, 3×30 mL). Chromatography over silica gel using 5% MeOH in CH2Cl2 as eluent furnished the 282 mg of the desired compound 6.6 as a yellow solid (yield: 77.8%). 1H NMR (300 MHz, DMSO-d6) δ 10.67 (br s 1H, NH), 8.32 (s, 1H, H-4), 7.86 (s, 1H, H-1), 7.00 (d, J 12.6 Hz, H-8), 6.09 (s, 1H, H-1′), 5.63 (d, J 12.6 Hz, H-9), 5.16 (m, 3H, 3×OH), 3.95 (m, 1H, H-3′), 3.88-3.56 (m, 3H, H-4′, 2×H-5′), 0.73 (s, 3H, CH3); ES MS: 391.5 (M+CH3COO)−.

1. waitat −30° C. to −20° C. for 3 hr
2. customThe reaction was quenched by addition of methanolic/CH2Cl2 (1:1) (5 mL)
3. stirringthe resulting mixture stirred at −15° C. for 30 min.
4. customneutralized with aqueous ammonia at 0° C.
5. stirringstirred at room temperature for 15 min
6. filtrationThe solid was filtered
7. washwashed with CH2Cl2/MeOH (1/1, 3×30 mL)

ORD record

ord-831a916ed03148e2b3e15096b6c18b98

Source dataset

uspto-grants-2007_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07268119B2