Methanol → Methyl chrysanthemate

To a mixture containing 430 g of methanol and 265 g of pyridine, under ice cooled conditions, 501.9 g of 3-(2-methyl-1-propenyl)-2,2-dimethylcyclopropanecarboxylic chloride {wherein the molar ratio of the (1R)-trans compound: (1R)-cis compound: (1S)-trans compound: (1S)-cis compound was 93.9:2.5:3.5:0.1} was added over 2.5 hours while stirring the reaction mixture. Subsequently, the reaction mixture was further stirred at room temperature over 4 hours. After concentrating the reaction mixture under reduced pressure to about half of its volume, the reaction mixture was eye-dropped into 500 ml of 3.5% hydrochloric acid. The resulting mixture was extracted 3 times with 200 ml of methyl-t-butyl ether and then concentrated to provide a residue. The resulting residue was distilled under reduced pressure (84 to 89° C./7 mmHg) to provide 426 g of methyl 3-(2-methyl-1-propenyl)-2,2-dimethylcyclopropanecarboxylate.

1. additionwas added over 2.5 hours
2. stirringSubsequently, the reaction mixture was further stirred at room temperature over 4 hours
3. concentrationAfter concentrating the reaction mixture under reduced pressure to about half of its volume
4. additionthe reaction mixture was eye-dropped into 500 ml of 3.5% hydrochloric acid
5. extractionThe resulting mixture was extracted 3 times with 200 ml of methyl-t-butyl ether
6. concentrationconcentrated
7. customto provide a residue
8. distillationThe resulting residue was distilled under reduced pressure (84 to 89° C./7 mmHg)

ORDレコード

ord-d14a4e05453c4efe80d26a9dffedf8c3

出典データセット

uspto-grants-2003_05

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US06562853B2