Triisopropyl borate → 3-(1-Adamantyl)-4,5-methylenedioxyphenylboronic acid

Temperature

-78 °C

To a solution of 4-(1-adamantyl)-6-bromobenzo[1,3]dioxole (2.10 g, 6.26 mmol) in THF (11 mL) at −78° C. (dry ice/acetone bath) under argon was added 1.6 M n-BuLi (10.0 mmol) in hexane (6.26 mL) in one portion. This mixture was stirred at −78° C. for 15 min. Tri(isopropyl)borate (4.30 mL, 18.8 mmol) was added, and the resulting solution was stirred at −78° C. for 20 min more before being allowed to warm to room temperature with stirring overnight. The mixture was quenched with 1 N HCl (40 mL) and then extracted with EtOAc (100 and 40 mL). The combined organic extracts were washed with brine and dried. Solvents were removed at reduced pressure, and the residue was washed with hexane and dried to give 1.23 g (65%) of 3-(1-adamantyl)-4,5-methylenedioxyphenylboronic acid as a cream solid, mp 258-261° C. IR 3231, 2903, 2849, 1343, 1164 cm−1; 1H NMR δ (CDCl3) 1.81 (bs, 6H, AdCH2), 2.13 (bs, 9H, AdCH2 and AdCH), 6.02 (s, 2H, CH2), 7.48 (s, 1H, 6-ArH), 7.75 ppm (s, 1H, 2-ArH).

1. stirringthe resulting solution was stirred at −78° C. for 20 min more
2. temperatureto warm to room temperature
3. stirringwith stirring overnight
4. customThe mixture was quenched with 1 N HCl (40 mL)
5. extractionextracted with EtOAc (100 and 40 mL)
6. washThe combined organic extracts were washed with brine
7. customdried
8. customSolvents were removed at reduced pressure
9. washthe residue was washed with hexane
10. customdried

ORD record

ord-a45ab3e3acd549bc9ae2e1e746296383

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09096544B2