Carbon Dioxide → (4-t-Butylphenylthio)nitromethane

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A 1.6 M solution of butyllithium in hexane (51.25 ml, 82 mmol) was added dropwise to a stirred solution of B (9.07 g, 40.5 mmol) in anhydrous tetrahydrofuran (150 ml) maintained a -40° C. under an atmosphere of argon. When the addition was complete, the mixture was stirred for 1 hour at -5° C. Propyl nitrate (12.92 g, 123 mmol) was added dropwise to the stirred mixture at -5° C., which was then stirred for a further 2 hours, maintaining the temperature below 0° C. throughout. The mixture [containing the dilithium salt of 2-(4-t-butylphenylthio) 2-nitroacetic acid]was acidified to pH 2 by addition of 2M hydrochloric acid. The mixture was allowed to stand for 30 minutes at ambient temperature after which time evolution of carbon dioxide [obtained from decarboxylation of 2-(4-t-butylphenylthio) 2-nitroacetic acid] had ceased. Water (300 ml) was then added and the mixture was extracted with ethyl acetate. The combined extracts were washed successively with an aqueous solution of sodium hydrogen carbonate, water and brine, and then dried (MgSO4) and the solvent removed by evaporation. The residual oil was purified by chromatography on silica, eluting with (3:20 v/v) ethyl acetate/hexane, to give (4-t-butylphenylthio)nitromethane (A) as an orange oil (4.76 g), NMR spectrum (200 MHz, d6DMSO): 1.27 (s, 9H), 6.02 (s, 2H), 7.42 (s, 4H).

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