Preparation and application of 1-methylcyclopropanemethanol_Industrial additives

Background and overview^[1]

1-Methylcyclopropanemethanol is an organic intermediate that can be prepared from 1-methylcyclopropanecarboxylic acid in one step.

Preparation^[1]

Dissolve 1-methylcyclopropanecarboxylic acid (100g) in tetrahydrofuran (1.31L). After stirring, add sodium borohydride (34g) in small portions. Boron trifluoride diethyl ether complex (170 g) was slowly added dropwise thereto, and the mixture was stirred at room temperature for 3 days. After 3 days, the reaction solution was poured into ice water, and the precipitated solid was filtered out. The tetrahydrofuran was distilled off under reduced pressure, extracted with dichloromethane, and dried with sodium sulfate. After drying, the solvent was distilled off under reduced pressure to obtain 1-methylcyclopropylmethanol (70 g).

Apply^[1]

CN201480044197.7 reported that 1-methylcyclopropane methanol can be used to prepare 1-(bromomethyl)-1-methylcyclopropane, and 1-(bromomethyl)-1-methylcyclopropane can be used Preparation of compound 1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-5-((1-methylcyclopropyl)methylamino ) Pyrazole-4-nitrile, this compound has a broad herbicidal spectrum and shows excellent herbicidal efficacy against important weeds with high leaf age. On the other hand, it is fully safe for cultivated crops. The preparation method of 1-(bromomethyl)-1-methylcyclopropane is as follows: the obtained (1-methylcyclopropyl)methanol (70g) is dissolved in dichloromethane (1.51L) and stirred. Carbon tetrabromide (371g) was added thereto, the reaction solution was cooled with an ice bath, triphenylphosphine (294g) dissolved in dichloromethane (500ml) was slowly added dropwise, and the reaction was carried out at room temperature for 2 days. After the reaction was completed, the solvent was distilled off, N,N-dimethylformamide (300 ml) was added and distilled under reduced pressure to obtain 1-(bromomethyl)-1-methylcyclopropane (72 g).

Main reference materials

[1] [China invention, China invention authorization] CN201480044197.7 Substituted pyrazolyl pyrazole derivatives and their use as herbicides