Toluene → alpha-Cypermethrin 1-Epimeric Mixture

Temperatur

70 °C

Cis-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (199 g, 0.95 M) was added to a solution of potassium carbonate (65.6 g, 0.475 M) in water (450 ml). Toluene (900 ml), tetra-n-butylammonium bromide (13.5 g, 0.05 M) and alpha-cyano-3-phenoxybenzyl p-toluenesulphonate (341 g, 0.9 M; prepared as described in A above) were added to the stirred mixture which was then heated at 70° C. for 3 hours. The mixture was cooled to ambient temperature and the organic phase was separated off, washed with aqueous potassium carbonate solution (2×200 ml) and water (2×200 ml), evaporated and degassed under vacuum to leave cis-alpha-cyano-3-phenoxybenzyl 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate as a pale amber oil (364 g, 97.3%), containing less than 1% trans-isomers.

1. customprepared
2. additionwere added to the stirred mixture which
3. temperatureThe mixture was cooled to ambient temperature
4. customthe organic phase was separated off
5. washwashed with aqueous potassium carbonate solution (2×200 ml) and water (2×200 ml)
6. customevaporated
7. customdegassed under vacuum

ORD-Eintrag

ord-bb5b25184ed94f6b82d54a5d9de5e618

Quelldatensatz

uspto-grants-1983_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04409150