Hydrogen phosphonates and polymer compositions containing them as flame retardants

The compound ##STR28##

The compound ##STR29##

The compound ##STR30##

Process for the preparation of cyclic hydrogenphosphonate which comprises admixing at 10.degree. C to 100.degree. C, formic acid with a cyclic phosphorochloridite having the formula ##STR31## where R is an alkylene, or haloalkylene group of a 1,2-glycol having from 2 to 8 carbon atoms, or of a 1,3-glycol having from 3 to 8 carbon atoms, and Z is Cl or Br.

Process for the preparation of the compound ##STR32## which comprises admixing at 10.degree. to 100.degree. C, formic acid with -chloro-5,5-bis(bromomethyl)-1,3,2-dioxaphosphorinane, ##STR33##

Process for the preparation of the compound ##STR34## which comprises admixing at 10.degree. to 100.degree. C, formic acid with

• . 9-dichloro-2,4,8,10-textraoxa-3,9-diphosphaspiro[5.5]undecane.

Process for the preparation of cyclic phosphorus compounds which comprises admixing at 10.degree. to 100.degree. C, formic acid with a phosphorochloridite selected from the group consisting of 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane, and 2-chloro-5-ethyl-5-methyl-1,3,2-dioxaphosphorinane, and 2-bromo-5,5-bis-(chloromethyl)-1,3,2-dioxaphosphorinane, and 2-chloro-4-methyl-1,3,2-dioxaphosphorinane, and 2-chloro-5-phenyl-1,3,2-dioxaphosphorinane, and 2-chloro-5-(4-fluoro-3-bromophenyl)-1,3,2-dioxaphosphorinane, 2-chloro-5,5-bis(bromomethyl)-1,3,2-dioxaphosphorinane, 3,9-dichloro-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane.

Process for the preparation of a cyclic phosphorus compound which comprises admixing at 10.degree. to 100.degree. C, formic acid with a cyclic phosphorochloridite having the formula ##STR35## where R is an alkylene, or haloalkylene group of a 1,2-glycol having from 2 to 8 carbon atoms, or of a 1,3-glycol having from 3 to 8 carbon atoms, and Z is Cl or Br, and thereafter treating the reaction mixture with a sulfenyl chloride, (R.sub.c) SCl, where R.sub.c is phenyl with 0 to 5 halogen atoms, or phenyl with 0 to 2 groups, or methyl with 0 to 3 chlorine atoms.

Process for the preparation of a cyclic phosphorus compound which comprises admixing at 10.degree. to 100.degree. C, formic acid with a cyclic phosphorochloridite having the formula ##STR36## where R is an alkylene, or haloalkylene group of a 1,2-glycol having from 2 to 8 carbon atoms, or of a 1,3-glycol having from 3 to 8 carbon atoms, and Z is Cl or Br, and thereafter treating the reaction mixture with a ketone, ##STR37## where R.sub.d is an alkyl radical of 1 to 4 carbon atoms, or phenyl.

Process for the preparation of a cyclic phosphorus compound which comprises admixing at 10.degree. to 100.degree. C, formic acid with a mixture of a cyclic phosphorochloridite having the formula ##STR38## where R is an alkylene, or haloalkylene group of a 1,2-glycol having from 2 to 8 carbon atoms, or of a 1,3-glycol having from 3 to 8 carbon atoms, and Z is Cl or Br, and a ketone, ##STR39## where R.sub.d is an alkyl radical of 1 to 4 carbon atoms or phenyl