반응 #8695

반응 방정식

EA

K3PO4

1-bromo-2,4-dimethyl-benzene

→

2-(2,4-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 96 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
6. 6
   workup.DISTILLATIONfollowed by distillation (bp 95–100° C. at 0.064 mbar)

실험 절차

(In analogy to a procedure given in J. Am. Chem. Soc. 122 (2000), 1360–1370.) To a suspension of Pd(OAc)2 (758 mg), 2-(di-tert.-butlylphosphino)-biphenyl (2.02 g) and K3PO4 (65.95 g) in THF (350 ml) dimethylmalonate (21.42 g) and 1-bromo-2,4-dimethyl-benzene (25 g) was added under argon. The mixture was refluxed for 96 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 followed by distillation (bp 95–100° C. at 0.064 mbar) to give 2-(2,4-dimethyl-phenyl)-malonic acid dimethyl ester (5.66 g) as a colourless oil. 1H-NMR(300 MHz, CDCl3): 2.30(s, 6H), 3.75(s, 6H), 4.87(s, 1H), 6.98–7.05(m, 2H), 7.25–7.28(m, 1H).

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