Реакция #49844

Уравнение реакции

HOAc

MgBr2

aldehyde

2-Benzyloxy acetaldehyde

1,3-bis(trimethylsilyloxy)-1,3-butadiene

→

title compound

Выход 60.0%

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

Выход 60.0%

Растворители

THF

Условия реакции

Обработка

1. 1
   Экстракцияextracted with Et2O (2×)
2. 2
   ДругоеAfter the ether was evaporated
3. 3
   workup.WAITAfter 3 hours
4. 4
   Промывкаthe solution was washed with H2O, saturated NaHCO3, and brine
5. 5
   Сушкаfinally dried over MgSO4

Методика

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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