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ChemicalBook CAS DataBase List 5,6-Dihydro-2-methyl-2H-pyran
55230-25-6

5,6-Dihydro-2-methyl-2H-pyran synthesis

11synthesis methods
-

Yield:55230-25-6 50.6%

Reaction Conditions:

in tetrahydrofuran at 240; for 6 h;Autoclave;

Steps:

1 Example 1Synthesis of 2-Methyl-5,6-dihydro-2H-pyran (II)

1000ml autoclave; 75g paraformaldehyde, 225g piperylene, 225g tetrahydrofuran, 1.5g hydroquinone;Close the autoclave. Under stirring, heated to 240°C and reacted for 6 hours. Cool to room temperature and withdraw material. Unreacted piperylene and solvent tetrahydrofuran are recovered at normal pressure. Distillation under reduced pressure gave 123.97 g of a colorless liquid; yield 50.6%.

References:

CN104370868,2017,B Location in patent:Paragraph 0021; 0022; 0023