Ammonium Chloride → 3-Ethyl-6-[(Z)-2-(3,4,5-trimethoxyphenyl)vinyl]-1,2-di(tert-butyldimethylsilyloxy)benzene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A suspension of 3,4,5-trimethoxybenzyltriphenylphosphonium bromide (3.9 g, 7.5 mmol) in tetrahydrofuran (40 mL) was cooled to 0° C. and butyllithium (4.7 mL of a 1.6 N solution in hexane, 7.5 mmol) was added dropwise. The brick red solution was stirred at 0° C. for 20 min, then a solution of 12 (2 g, ca 5 mmol) in tetrahydrofuran (15 mL) was added dropwise. The temperature was allowed to rise to room temperature over 4 hours, than the reaction was poured into ethyl acetate (ca 150 mL) and NH4Cl sat (ca 100 mL) the phases separated and the organic layer re-extracted with AcOEt. The combined organic extracts were washed with brine, dried over sodium sulphate and the solvent removed under reduced pressure to give a crude which was purified by column (cyclohexane:AcOEt 9:1) to give 0.6 g of 13:

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