undec-2-enal

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 37.78 g of ethyl orthoformate (13.09 ml, 356 mmol, 2 eq.) and 1.691 g of para-toluenesulfonic acid (catalytic amount: 8.9 mmol, 0.051 eq.) are added to a solution of 30.05 g of 97% undecenal (37.10 ml, 173 mmol) dissolved in 500 ml of methanol. The reaction takes place over 12 hours and at reflux of the methanol. After addition of 500 ml of dichloromethane, the reaction mixture is washed successively with a 1% sodium carbonate solution (two times) and with a saturated sodium chloride solution, dried over anhydrous magnesium sulfate and then concentrated to give 36.39 g of a brown liquid with a yield of 97%. over 12 hours the reaction mixture is washed successively with a 1% sodium carbonate solution (two times) and with a saturated sodium chloride solution dried over anhydrous magnesium sulfate concentrated