반응 #1606336

반응 방정식

(2-cyclobutyl-6-fluorophenoxy)(tert-butyl)dimethylsilane

B(O-iPr)3

n-BuLi

Acetic acid

2,2,6,6-tetramethylpiperidine

→

(3-((tert-butyldimethylsilyl)-oxy)-4-cyclobutyl-2-fluorophenyl)boronic acid

수율 88.1%

용매

THF

THF

water

반응 조건

후처리

1. 1
   온도warmed up to 0° Celsius for 40 min
2. 2
   온도After 40 min the reaction mixture was cooled to −78° Celsius
3. 3
   workup.ADDITIONwas added over the course of 2 min
4. 4
   온도warmed to 0° Celsius
5. 5
   온도the reaction was warmed to room temperature
6. 6
   추출The resultant mixture was extracted with ethyl acetate
7. 7
   건조The organic portion was dried over sodium sulfate
8. 8
   농축concentrated to dryness

실험 절차

A 100 mL three neck round-bottomed flask, equipped with a stir bar, temperature probe and nitrogen inlet, was charged with 2,2,6,6-tetramethylpiperidine (1.7 mL, 10 mmol) and THF (10 mL). The mixture was cooled to −78° Celsius and treated with 2.5 M n-BuLi (4.1 mL, 10 mmol). The resultant mixture was stirred for 5 min and then warmed up to 0° Celsius for 40 min. After 40 min the reaction mixture was cooled to −78° Celsius and treated with B(O-iPr)3 (13.0 mL, 10.2 mmol) over the course of 10 min. After stirring for 20 min a solution of (2-cyclobutyl-6-fluorophenoxy)(tert-butyl)dimethylsilane (1.8 g, 6.3 mmol) in THF (4 mL) was added over the course of 2 min. The reaction was stirred at −78° Celsius for 2 hours and then warmed to 0° Celsius. Acetic acid (3.6 mL, 64 mmol) is added and the reaction was warmed to room temperature and diluted with water. The resultant mixture was extracted with ethyl acetate. The organic portion was dried over sodium sulfate and concentrated to dryness to provide (3-((tert-butyldimethylsilyl)-oxy)-4-cyclobutyl-2-fluorophenyl)boronic acid (1.8 g, 86%). 1H NMR (500 MHz, CDCl3), δ 7.39-7.32 (m, 1H), 7.18-7.13 (m, 1H), 5.10-4.97 (m, 2H), 3.82 (t, J=8.8 Hz, 1H), 2.41-2.06 (m, 5H), 2.03-1.95 (m, 1H), 1.03 (s, 9H), 0.19 (s, 6H).

출처