Acetic Acid Mixture with Hydrobromic Acid → HCID 23582254, compound
Reaction equation
[CH3:1][O:2][C:3](=[O:18])[C:4]([C:16]#[N:17])=[CH:5][C:6]([CH2:10][CH2:11][O:12]C(=O)C)=[CH:7]OC.[BrH:19].CC(O)=O>C(O)(=O)C>[Br:19][C:16]1[C:4]([C:3]([O:2][CH3:1])=[O:18])=[CH:5][C:6]([CH2:10][CH2:11][OH:12])=[CH:7][N:17]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 35 °C
Procedure
Into a 1L three-neck round-bottom flask with a stirrer bar, nitrogen inlet and condenser were added 20 g (78.974 mmol) of methyl-4-(2-acetyloxyethyl)-2-cyano-5-methoxypenta-2,4-dienoate, which was dissolved in 55 ml acetic acid and heated to 35° C. The solution was slowly treated over a period of ½ h with 85.21 g (237 mmol) HBr/HOAc at 35-40° C. with occasional cooling. After the addition was completed the solvents were evaporated at 40° C. and 30 mm Hg and the residue was charged while stirring with a mixture of 60 ml water and 15 ml methanol. The reaction mixture was treated with 3.3 g charcoal and heated for ½ h at 40° C. The charcoal was filtered off and the methanol was distilled off under reduced pressure. The reaction mixture was evaporated and the residue was chromatographed at 100 g silica gel using a solvent mixture of Heptane:Ethyl acetate (2:1 v/v).