Reaktion #61293

Reaktionsgleichung

6-[6-methoxy-7-methyl-3-oxo-4-(2-trimethylsilanyl-ethoxy)-1,3-dihydro-isobenzofuran-5-yl]-4-methyl-hex-4-enoic acid methyl ester

sodium hydroxide

HCl

→

desired product

Ausbeute 83.0%

6-[6-Methoxy-7-methyl-3-oxo-4-(2-trimethylsilanyl-ethoxy)-1,3-dihydro-isobenzofuran-5-yl]-4-methyl-hex-4-enoic acid

Ausbeute 83.0%

Lösungsmittel

methanol

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   FiltrationThe precipitate was collected by suction filtration
2. 2
   Waschenwashed with water

Vorschrift

A mixture of 6-[6-methoxy-7-methyl-3-oxo-4-(2-trimethylsilanyl-ethoxy)-1,3-dihydro-isobenzofuran-5-yl]-4-methyl-hex-4-enoic acid methyl ester (1.5 g, 3.45 mmol) and sodium hydroxide (552 mg) in a mixture of methanol (20 mL) and water (7 mL) was stirred at room temperature for one hour. The solution was acidified with 1N HCl. The precipitate was collected by suction filtration and washed with water to give the desired product (1.2 g, 83%). 1H NMR (300 MHz, CDCl3) δ 0.02 (s, 9H), 1.15-1.22 (m, 2H), 1.76 (s, 3H), 2.13 (s, 3H), 2.12-2.28 (m, 2H), 2.35-2.41 (m, 2H), 3.37 (d, 2H, J=7 Hz), 3.71 (s, 3H), 4.22-4.28 (m, 2H), 5.07 (s, 2H), 5.13-5.17 (m, 1H) ppm; MS (m/z) 419.3 [M−H]−, 443.2 [M+Na]+.

Quelle