Acetic Acid → 6-Benzyloxymethyl-2-methyl-5,6-dihydro-4H-pyran-4-one

Beteiligte Stoffe

Reaktionsschritte

A solution of 10.4 g of the aldehyde from Step 1 in 250 ml of THF was cooled to 0° C. and 1.0 eq of freshly prepared MgBr2 was added dropwise. The mixture was warmed to r.t. and 40.6 g of 1,3-bis(trimethylsilyloxy)-1,3-butadiene (Emde, et al., Synthesis p. 6 (1982)) was added. After 3.0 h, 50% aqueous HOAc was added and the mixture was stirred 10 min and then extracted with Et2O (2×). After the ether was evaporated, the resultant oil was taken back up in 300 ml of CH2Cl2 and 12 ml of TFA. After 3 hours, the solution was washed with H2O, saturated NaHCO3, and brine and finally dried over MgSO4. After flash chromatography, 9.5 g (60%) of the title compound was obtained.

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