Preparation and application of (S)-(3-phenoxyphenyl)hydroxyacetonitrile_Kain Industrial Additive

Background and overview^[1]

(S)-(3-phenoxyphenyl)hydroxyacetonitrile is a pesticide intermediate that can be used to prepare fluvalinate. Flufenacrin is mainly used in the control of major pests including Lepidoptera, Coleoptera, Homoptera, Diptera and Thysanoptera on crops such as cotton, fruit trees, vegetables, corn, tea, tobacco and so on. It is very important to health. It is also effective against pests such as house flies, Culex pipiens, German cockroaches, etc. Compared with other pyrethroids, it has significant miticidal effect.

Preparation^[1]

First add 0.5g (1.88mmol) S-cyanohydrin acetate into the Erlenmeyer flask, then add 87ul (0.94mmol) BuOH, 0.05mg Candida antarctic lipase (NOVO 435) and 10ml isopropyl ether , placed in a shaker at 10°C for 72 hours. Then concentrate the reaction solution to dryness, dissolve it with 20 ml of a mixed solution (composed of 6 ml of water, 14 ml of methanol, and 6 ml of benzene), separate the layers, remove the lower solution, and use 10 ml of a mixture of benzene and methanol (the volume ratio of benzene and methanol is 7 :3) Extract twice, evaporate part of the methanol, add EA to remove the water layer, dry the EA layer and concentrate to obtain 0.06g of (S)-(3-phenoxyphenyl)hydroxyacetonitrile.

Apply^[1]

Preparation of (R, S) fluvalinate: Dissolve 1.31g (0.00444mol) chrysanthemic acid with an appropriate amount of EA, then add the mixed solution to 1.0g (0.00444mol) (S)-(3- Phenoxyphenyl)hydroxyacetonitrile in ice bath with stirring. Then add 0.90g (0.00444mol) DCC and 0.05g (0.00444mol×10%) DMAP in sequence and stir in ice bath for 4h. Filter, add EA to the filtrate and dilute to 50 ml, wash with 5% NaOH and 3% HCl three times each, then wash with saturated brine until neutral, then dry with anhydrous sodium sulfate, filter, and finally use pre-cooled CH₂Cl₂ is washed and dried to obtain 1.66g of chiral (R, S) cyhalothrin.

References

[1] [Chinese invention, Chinese invention authorization] CN201110226297. S) Application of fluvalinate in preventing and controlling Varroa mites [Authorized]