Tetrahydrofuran → (Z)-1-(2-(acetoxymethyl)-4-(tert-butoxycarbonylamino)-3-methylphenyl)-3-methoxy-3-oxoprop-1-en-2-yl benzoate

Participants

Reaction Steps

3-(tert-butoxycarbonylamino)-6-iodo-2-methylbenzyl acetate (18.0 g, 44.4 mmol) in tetrahydrofuran (180.00 ml, 2197 mmol) was added triethylamine (24.76 ml, 178 mmol) followed by tetrabutylammonium chloride, hydrate (13.15 g, 44.4 mmol) and 3-methoxy-3-oxoprop-1-en-2-yl benzoate (11.91 g, 57.7 mmol). After introducing nitrogen atmosphere, palladium(II)acetate (0.898 g, 4.0 mmol) was added. The reaction mixture was refluxed for 3 h. The crude product was cooled and most of the solvent was removed. The crude product was diluted with ether (300 mL) and solids were removed by filtration. The solvent was evaporated and the crude product was purified by flash chromatography using 30% EtOAc in hexane to 50% EtOAc in hexane. The product was crystallized from a mixture of EtOAc-hexane to give a white powder of (Z)-1-(2-(acetoxymethyl)-4-(tert-butoxycarbonylamino)-3-methylphenyl)-3-methoxy-3-oxoprop-1-en-2-yl benzoate (20.5 g, 42.4 mmol, 95% yield). 1H NMR (500 MHz, CDCl3): in δ 8.08-8.06 (m, 2H), 7.75-7.74 (m, 2H), 7.60-7.58 (m, 1H), 7.49-7.44 (m, 3H), 5.25 (s, 2H), 3.85 (m, 3H), 2.24 (s, 3H), 2.07 (s, 3H), 1.52 (s, 9H); MS (ESI) 506 (M+H); Rf=2.61.

Provenance & Evidence