반응 #666858

반응 방정식

2-isopropoxy-4,4,5,5-tetramethyl-[1,3,2]-dioxaborolane

3

3-bromo-9-(2-methylpropyl)carbazole

BuLi

→

4

수율 81.4%

2-(9-(2-methylpropyl)carbazol-3-yl)-4,4,5,5-tetramethyl-[1,3,2]-dioxaborolane

수율 81.4%

용매

THF

반응 조건

후처리

1. 1
   workup.ADDITIONwas added in one portion
2. 2
   기타quenched with water
3. 3
   추출extracted with ether
4. 4
   세척washed with brine and water
5. 5
   건조dried over MgSO4
6. 6
   기타Upon evaporating off the solvent
7. 7
   기타the crude product was purified by column chromatography on silica gel with hexane/methylene chloride 3:1 (v/v) as the eluent

실험 절차

Into a solution of 3 (4.2 g, 13.9 mmol) in THF (80 ml) was added BuLi (2.5 M in hexane, 6.95 ml, 17.4 mmol) dropwise at −78° C. The mixture was stirred at this temperature for 3 hours before 2-isopropoxy-4,4,5,5-tetramethyl-[1,3,2]-dioxaborolane (4.05 g, 21.75 mmol) was added in one portion. The reaction mixture was allowed to warm up to room temperature over a period of 12 hours, quenched with water, and then extracted with ether. The organic extracts were combined, washed with brine and water, and dried over MgSO4. Upon evaporating off the solvent, the crude product was purified by column chromatography on silica gel with hexane/methylene chloride 3:1 (v/v) as the eluent to yield 4 (3.95 g, 81%) as a white powder. 1H NMR (400 MHz, CDCl3, 298 K): δ(ppm) 8.60 (s, 1H), 8.15-8.10 (d, 1H), 7.90-7.85 (d, 1H), 7.45-7.35 (m, 3H), 7.25-7.15 (m, 1H), 4.10-4.09 (d, 2H), 2.42-2.30 (m, 1H), 1.39 (s, 12H), 0.97-0.95 (d, 6H).

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