Patent · US Expired

Synthesis of tetraalkyl vinylidene diphosphonate monomer

US5256808A · kind A · utility

9Cited by
2References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 4, 1992
Grant dateOct 26, 1993
Priority date
Expiry dateDec 4, 2012

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07F9/4031
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A method of making a monomer of tetraalkyl vinylidene-1, 1-diphosphonate. The monomer is manufactured by combining an aqueous secondary amine solution with a formaldehyde and a tetra (alkyl) methylene diphosphonate. The resulting mixture is maintained at a pH above about 6 and refluxed for two hours to enable reaction to produce the monomer of tetraalkyl vinylidene-1, 1-diphosphonate. The product monomer is then purified to produce the final end product.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.