CAS No.: 56181-66-9 | C22H20O | Intermediate of Difenacoum
- Difenacoum Stage 6 (before coumarin)
Mol. Formula: C22H20O
CAS No.: 56181-66-9
EC No.: 260-034-9
Purity in stock: ≥ 99.5%, 99.7% (2 bathes)
- IUPAC name: 3-[1,1′-biphenyl]-4-yl-1,2,3,4-tetrahydro-1-naphthol
China Reg. name: 3-[1,1′-biphenyl]-4-yl-1,2,3,4-tetrahydro-1-naphthol
China’s Regulatory: MEP Directive No. 7/2010
New Substances Registration No.: 2011009/MEP
Registration Date at China MEP: 12. JAN, 2011
Since 2005, China has terminated any new industrial projects involving rodenticides, including Difenacoum.
- According to the National Industrial Policy “Regulations on Promoting Industrial Structure Adjustment” that came into effect on December 2, 2005, and its detailed guidance document, “Directory for Guiding Industry Restructuring (2005)” (now updated to the 2024 edition), China prohibits the production of new highly toxic pesticides, including all rodenticide active ingredients.
- When the factory expansion was completed and put into operation in 2004, the brodifacoum and difenacoum production lines passed the environmental and safety assessments conducted by the authorities. In fact, the synthesis steps for brodifacoum and difenacoum are almost entirely identical, with the main difference being that bromine (4-bromobiphenyl) is not used in the initial stage.
- Unfortunately, the dossier we submitted to the Ministry of Agriculture (MOA) for registration had not yet passed the final review when the national industrial policy was introduced in 2005.
- As a result, over the past period, we have only produced some intermediates, which are currently intended solely for export use.
Rodenticide intermediates registered under China REACH
(C22H20O, the last intermediate before 4-hydroxycoumarin synthesis)
- “The Measures for Environmental Administration of New Chemical Substances” (Ministry of Environmental Protection (MEP) Decree No.7,) was issued in Jan 2010 and went into effect on Oct 15, 2010. This regulation is similar to EU REACH and is also known as ‘‘Chinese REACH.’’
https://www.gov.cn/gongbao/content/2010/content_1671246.htm - “The Measures for the Environmental Management Registration of New Chemical Substances” (Decree No. 11 of the Ministry of Ecology and Environment of China) was issued on February 17, 2020, replacing Decree No. 7 of the former Ministry of Environmental Protection.
https://www.mee.gov.cn/xxgk2018/xxgk/xxgk02/202005/t20200507_777913.html
- On January 12, 2011, the Difenacoum intermediate (C22H20O) produced by Siyang Rodenticide Factory completed registration in accordance with China’s REACH regulations of 2010.
- In addition, prior to the promulgation of the latest 2020 regulations, our factory had already ceased production. Currently, all inventory products are produced in full compliance with all relevant Chinese laws and regulations.
Stock
(available)
- Regarding the stock of Difenacoum intermediate 6: Unlike Brodifacoum, global usage of Difencam remains very low. As a result, we have exported very small quantities in the past, and as of 2025, we still have a certain amount of stock remaining.
