3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide
This is a specific non-halogenated organo-phosphorus compound featuring a spirocyclic structure with two phosphonate groups, classified under HTS 2931.48.00.00 as an organo-inorganic compound where phosphorus is directly linked to carbon. It is used primarily as a synthetic intermediate in pharmaceutical and agrochemical production.
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If containing arsenic or other nonmetal/metal directly linked to carbon
Organo-inorganic compounds with elements beyond phosphorus fall under the residual 'other' provision in 2931.90, later in numerical order per Chapter 29 note.
If imported as a mixture or solution exceeding Chapter 29 solvent allowances
Solutions not qualifying under Chapter 29 note (e) for transport/safety are classified as chemical preparations in Chapter 38.
If classified primarily by alcohol function rather than phosphorus
If the phosphorus is incidental and alcohol group dominates, it shifts to oxygen-function compounds in heading 2909 per Chapter notes on function priority.
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Import Tips & Compliance
• Provide detailed chemical analysis and purity certificates to confirm classification under Chapter 29 note (a) for separate chemically defined compounds
• Verify no halogenation to avoid misclassification into earlier headings
• Include safety data sheets (SDS) for hazardous material handling during customs clearance
Related Products under HTS 2931.48.00.00
Antioxidant 552 (3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide)
Antioxidant 552 is the commercial grade of 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide, a non-halogenated organo-phosphorus stabilizer for polymers. It falls under HTS 2931.48.00.00 due to its specific spiro phosphonate structure with P-C bonds, as defined in Chapter 29 heading 2931.
DOPO Derivative 3,9-Dimethylspiro Phosphonate
A DOPO-based derivative, this compound is precisely 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide, used in flame-retardant synthesis for electronics. Classified in HTS 2931.48.00.00 as a non-halogenated organo-phosphorus compound per Chapter 29 definitions.
Spiro Phosphonate Monomer for Polymer Synthesis
This research-grade spiro phosphonate monomer, chemically 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide, is used in copolymer production. It qualifies under HTS 2931.48.00.00 for its organo-inorganic phosphorus structure excluding halogens.
CAS 65481-32-7 3,9-Dimethylspiro[5.5]undecane Phosphonate Dioxide
Identified by CAS 65481-32-7, this is pure 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide, a building block for organophosphorus ligands. HTS 2931.48.00.00 covers it as a non-halogenated organo-phosphorus derivative.