تفاعل #1833250

معادلة التفاعل

Benzo[d][1,3]dioxole

sec-Butyllithium

2-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

→

title compound

المردود 34.5%

2-(Benzo[d][1,3]dioxol-4-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

المردود 34.5%

المذيبات

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   أخرىthe temperature below −100° C
2. 2
   أخرىthe temperature below −100° C
3. 3
   درجة الحرارةto warm to room temperature
4. 4
   أخرىpartitioned between diethyl ether and water
5. 5
   استخلاصThe organic phase was extracted with water once again
6. 6
   استخلاصThe product was extracted with diethyl ether
7. 7
   أخرىthe organic phase was dried
8. 8
   تركيزconcentrated under vacuum
9. 9
   أخرىThe product was purified by flash chromatography (silica gel)

الإجراء التجريبي

Benzo[d][1,3]dioxole (3.05 g, 25 mmol) was dissolved in tetrahydrofuran (50 mL) and cooled to −108° C. utilizing a tetrahydrofuran/liquid nitrogen bath. sec-Butyllithium (1.4 M in cyclohexane; 19.64 mL, 27.5 mmol) was added dropwise, keeping the temperature below −100° C. The reaction mixture was then stirred at temperatures between −100° C. and −108° C. for 2 h to ensure complete deprotonation. 2-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (4.65 g, 25.00 mmol) was then added to the reaction mixture dropwise, keeping the temperature below −100° C. The reaction mixture was then allowed to warm to room temperature and partitioned between diethyl ether and water. The organic phase was extracted with water once again and the aqueous phases combined and acidified to pH 4 with HCl. The product was extracted with diethyl ether and the organic phase was dried and concentrated under vacuum. The product was purified by flash chromatography (silica gel) to provide the title compound as a white solid (2.14 g, 34.5%): 1H NMR (300 MHz, CDCl3) δ 7.21 (dd, J=7.6, 1.4 Hz, 1H), 6.90 (dd, J=7.7, 1.5 Hz, 1H), 6.82 (t, J=7.6 Hz, 1H), 6.02 (s, 2H), 1.36 (s, 12H); EIMS m/z 248.

المصدر