반응 #8694

반응 방정식

K3PO4

1-bromo-3,4-dimethyl-benzene

EA

→

2-(3,4-dimethyl-phenyl)-malonic acid dimethyl ester

용매

THF

반응 조건

후처리

1. 1
   workup.ADDITIONwas added under argon
2. 2
   온도The mixture was refluxed for 16 h
3. 3
   여과filtered
4. 4
   기타The filtrate was evaporated
5. 5
   기타the resulting brown oil was purified on silica gel eluting with heptane:EA 4:1 to 1:1

실험 절차

(In analogy to a procedure given in J. Am. Chem. Soc. 122 (2000), 1360-1370.) To a suspension of Pd(OAc)2 (455 mg), 2-(di-tert.-butylphosphino)-biphenyl (1.21 g) and K3PO4 (39.6 g) in THF (200 ml) dimethylmalonate (12.85 g) and 1-bromo-3,4-dimethyl-benzene 15.0 g) was added under argon. The mixture was refluxed for 16 h, cooled to rt and diluted with EA (300 ml) and filtered. The filtrate was evaporated and the resulting brown oil was purified on silica gel eluting with heptane:EA 4:1 to 1:1 to give 2-(3,4-dimethyl-phenyl)-malonic acid dimethyl ester (16.2 g) as a colourless oil which slowly crystallises. 1H-NMR (300 MHz, CDCl3): 2.25(s, 3H), 2.26(s, 3H), 3.75(s, 6H), 4.59(s, 1H), 7.10–7.20(m, 3H).

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