Reaktion #326219

Reaktionsgleichung

LDA

103b

t-Butyl 1-(4-bromo-butyl)-cyclopropanecarboxylate

butyl cyclopentanecarboxylate

1,5-dibromopentane

→

Compound 103f

Butyl 1-(5-bromo-pentyl)-cyclopentanecarboxylate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeto give
2. 2
   Sonstigeafter purification
3. 3
   workup.DISTILLATIONby fractional distillation under reduced pressure, 3f (49.1 g, 93% pure by GC, 61%) as a bright yellow liquid
4. 4
   SonstigeT=123° C. (p=0.001 Torr)

Vorschrift

Compound 103f was prepared, likewise the procedure described for 103b, starting from butyl cyclopentanecarboxylate (40.2 g, 0.236 mol), 1,5-dibromopentane (64 mL, 0.45 mol) and LDA (2 M in THF/heptane/ethylbenzene, 200 mL, 0.40 mol) to give, after purification by fractional distillation under reduced pressure, 3f (49.1 g, 93% pure by GC, 61%) as a bright yellow liquid. bp: T=123° C. (p=0.001 Torr). 1H NMR: δ 4.06 (t, J=6.6 Hz, 2H), 3.38 (t, J=6.9 Hz, 2H), 2.15-2.07 (m, 2H), 1.89-1.79 (quintet, J=7.1 Hz, 2H), 1.69-1.56 (m, 8H), 1.49-1.32 (m, 6H), 1.28-1.17 (m, 2H), 0.94 (t, J=7.4 Hz, 3H). 13C NMR: δ 177.7, 64.0, 54.0, 39.0, 36.0 (2×), 33.6, 32.5, 30.7, 28.5, 25.1, 24.8 (2×), 19.1, 13.6. HRMS calcd for C15H27BrO2 (M+): 318.1195, found: 318.1192.

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