Toluene → alpha-Cypermethrin 1-Epimeric Mixture

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Cis-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (1680 g, 8.04 M) was added to a solution of potassium carbonate (555 g, 4.02 M) in water (3800 ml). Toluene (7600 ml), tetra-n-butylammonium bromide (115 g, 0.4 M) and alpha-cyano-3-phenoxybenzyl p-toluenesulphonate (2902 g, 7.65 M; prepared as in Example 1(A) above) were added to the stirred mixture which was then heated at 70° C. for 5 hours. The mixture was cooled to ambient temperature and the organic phase was separated off, washed twice with aqueous potassium carbonate solution and twice with water, evaporated and degassed under vacuum to leave cis-alpha-cyano-3-phenoxybenzyl 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate as a yellow oil (3130 g, 99%), containing less than 1% trans-isomers.

Herkunft & Nachweise