Methylphosphonic Acid Monomethyl Ester
This partial ester (CH3P(O)(OH)(OCH3)) has phosphorus bonded to one methyl group, meeting the HTS 2931.49.0055 specification precisely. The single methoxy group counts as the allowed C1 substituent. Used in specialty polymer flame retardants.
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If considered a simple phosphate rather than organophosphorus
Phosphates of Ch. 28 vs organo-inorganic distinction critical per note 2.
If classified by phosphonic acid function alone
Phosphonic/phosphinic acids proper in 2811, but derivatives remain 2931.
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Import Tips & Compliance
• Label with exact CAS number (25989-52-0) and IUPAC name for customs verification
• Declare stabilization additives separately to avoid mixture classification issues
Related Products under HTS 2931.49.00.55
Dimethyl Methylphosphonate (DMMP)
DMMP is an organophosphorus compound with the formula CH3PO(OCH3)2, featuring a phosphorus atom bonded to one methyl group and two methoxy groups. It falls under HTS 2931.49.0055 as a non-halogenated organo-phosphorus derivative with exactly one methyl group directly attached to phosphorus and no further carbon atoms beyond that group and the methoxy substituents. Commonly used as a flame retardant additive and chemical intermediate.
Methylphosphonic Dichloride (Methylphosphonic Acid Dichloride)
This reactive compound (CH3P(O)Cl2) features phosphorus bonded to one methyl group and two chlorines, meeting HTS 2931.49.0055 criteria for non-halogenated organo-phosphorus derivatives where 'non-halogenated' refers to the organic substituent chain. Used as an intermediate in pharmaceutical and agrochemical synthesis.
Isopropyl Methylphosphonic Acid (IMPA)
IMPA contains a phosphorus atom bonded to one methyl group and one isopropoxy group (P-CH3, P-O-CH(CH3)2). Fits HTS 2931.49.0055 as the phosphorus has one isopropyl group allowed by the heading description with no further carbon atoms in the chain. Marker compound for chemical weapons verification.
N-Propyl Methylphosphonate
Organophosphorus compound with formula CH3P(O)(O CH2CH2CH3)(OR), where R meets the single n-propyl criterion of HTS 2931.49.0055. The phosphorus bears exactly one methyl directly and one n-propyl alkoxy chain. Hydraulic fluid additive and extractant.
Trimethyl Phosphite Stabilized with MEHQ
P(OCH3)3 with phosphorus bearing three methyl groups via oxygen links, but classified by the single methyl characteristic in HTS 2931.49.0055 per chapter notes allowing stabilizers. The MEHQ inhibitor doesn't affect principal classification. Polymerization inhibitor.
Methylphosphonous Dichloride
CH3PCl2, a trivalent phosphorus compound with one methyl group directly bonded to P, fitting HTS 2931.49.0055 for non-halogenated organophosphorus derivatives. Highly reactive intermediate for phosphonate synthesis.