Реакция #61231

Уравнение реакции

2-(4-bromo-but-2-enyl)-6-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydro-isobenzofuran-5-yl)-4-methyl-hex-4-enoic acid methyl ester

triethylphosphite

→

2-[4-(diethoxy-phosphoryl)-but-2-enyl]-6-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydro-isobenzofuran-5-yl)-4-methyl-hex-4-enoic acid methyl ester

Выход 44.5%

Растворители

toluene

Условия реакции

Обработка

1. 1
   Температураat reflux for 20 hours
2. 2
   КонцентрированиеThe mixture was concentrated
3. 3
   Другоеchromatographed on silica gel eluting with ethyl acetate (60% to 100%)/hexanes

Методика

A solution of 2-(4-bromo-but-2-enyl)-6-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydro-isobenzofuran-5-yl)-4-methyl-hex-4-enoic acid methyl ester 4B (140 mg, 0.30 mmol) and triethylphosphite (600 mg, 3.6 mmol) in toluene (30 mL) was stirred at reflux for 20 hours. The mixture was concentrated and chromatographed on silica gel eluting with ethyl acetate (60% to 100%)/hexanes, affording 2-[4-(diethoxy-phosphoryl)-but-2-enyl]-6-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydro-isobenzofuran-5-yl)-4-methyl-hex-4-enoic acid methyl ester 4C as an oil (70 mg, 43%); 1H NMR (300 MHz, CDCl3) δ 1.27 (m, 6H), 1.79 (s, 3H), 2.0-2.7 (m, 8H), 3.37 (d, J=6.6 Hz), 3.52 (s, 3H), 3.75 (s, 3H), 4.08 (m, 4H), 5.20 m, 3H), 5.45 (m, 2H) ppm.

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