Triphenylphosphine → (S)-methyl 5-methyl-2-(pent-4-en-2-yloxy)benzoate

Beteiligte Stoffe

Reaktionsschritte

To a solution of methyl 2-hydroxy-5-methylbenzoate (1.0 g, 6.02 mmol) in THF (14 ml) were added (R)-(−)-pent-4-en-2-ol (1.037 g, 12.04 mmol) and triphenylphosphine (2.052 g, 7.82 mmol). DIAD (1.521 ml, 7.82 mmol) was added dropwise (exotherm) and the mixture was stirred at rt. After 4.5 h, the mixture was diluted with Et2O and washed with 1N NaOH followed by water (3×'s) then brine, dried (Na2SO4), filtered and concentrated. The yellow oil was purified by flash chromatography (Biotage; 0%-100% EtOAc/hexane; 20 CV) to give (S)-methyl 5-methyl-2-(pent-4-en-2-yloxy)benzoate (1.2664 g, 5.41 mmol, 90% yield) as a yellow oil. 1H NMR (400 MHz, CDCl3) δ 7.58 (d, J=2.2 Hz, 1H), 7.23 (dd, J=8.3, 2.0 Hz, 1H), 6.90 (d, J=8.6 Hz, 1H), 6.03-5.77 (m, 1H), 5.21-4.99 (m, 2H), 4.61-4.35 (m, 1H), 3.89 (s, 3H), 2.60-2.46 (m, 1H), 2.46-2.34 (m, 1H), 2.34-2.25 (m, 3H), 1.34 (d, J=6.1 Hz, 3H).

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