Abstract: Process for the preparation of 6H-dibenzo [c,e][1,2]oxaphosphorin-6-one of the formula ##STR1## in which R.sup.1 and R.sup.2 are identical or different and are halogen or an alkyl or alkoxy group having from 1 to 6 carbon atoms and a and b are identical or different and are 0, 1, 2 or 3, which involves reacting a 6-chloro-(6H)-dibenzo[c,e][1,2]oxaphosphorin of the formula ##STR2## in which R.sup.1, R.sup.2, a and b are as defined above, with water in a molar ratio of 1:1 at from 50.degree. to 250.degree. C., in the presence if desired of a solvent, and separating off gaseous hydrogen chloride at the rate at which it is formed.

Abstract: Acylaminomethanephosphinic acids, and a process for the preparation of acylaminomethanephosphonic acids and acylaminomethylphosphinic acidsAcylaminomethanephosphonic acid and acylaminomethylphosphinic acids of the formula I,R.sup.2 --CO--NH--CH.sub.2 --P(O)(OH)R.sup.1 (I)in which R.sup.1 is hydroxyl, C.sub.1 -C.sub.4 -alkyl or phenyl and R.sup.2 is H, C.sub.1 -C.sub.6 -alkyl, benzyl or phenyl, unsubstituted or substituted by one or more radicals from the group comprising C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy and halogen, are valuable intermediates for the preparation of biologically active compounds.They can be prepared by reacting a compound of the formula IIR.sup.2 --CO--NH--CH.sub.2 --OH (II)with compounds of the formula III,H--P(O)(OH)R.sup.1 (III)in the presence of an at least equimolar amount of acetic anhydride, based on the compound of the formula II.The compounds of the formula (I) where R.sup.1 is other than hydroxyl, are novel.

Abstract: The invention relates to acyl-(2'-hydroxydiphenyl-2-yl)-phosphinic acid salts of formula (I) ##STR1## in which each of the radicals R.sup.1, R.sup.2 and R.sup.3 may be included singly or multiply and in which R.sup.1 and R.sup.2 are mutually independently hydrogen, an alkyl or alkoxy radical with 1 to 6 carbon atoms or halogen with an atomic number of 9 to 35; R.sup.3 means the same as R.sup.1 or R.sup.2 ; Ar is an aromatic hydrocarbon radical with 6 to 10 carbon atoms; and Me is a cation of at least one alkaline metal or N(R.sup.4).sub.4 + in which the radicals R.sup.4 are the same or different and stand for an alkyl radical with 1 to 6 carbon atoms. The invention also relates to a process for producing these compounds (I) and their use as photoinitiators in photopolymerisable materials, preferably on an aqueous basis.

Abstract: Process for preparing 6-chloro-(6H)-dibenz[c,e][1,2]oxaphosphorin of the formula (I), ##STR1## in which R.sup.1 and R.sup.2 are identical or different and are halogen, alkyl or alkoxy, each having from 1 to 6 carbon atoms, and a and b are integers from 0 to 3, preferably from 0 to 2, by reaction of o-phenylphenol of the formula (II), ##STR2## in which R.sup.1, R.sup.2, a and b are as defined above, with phosphorus trichloride in the presence of Lewis acids as catalysts with elimination of hydrogen chloride, wherein the phosphorus trichloride is metered into the mixture of compound (II) and Lewis acid at temperatures of 170.degree.-220.degree. C.

Abstract: A dibenzo-[c,e] [1,2] oxaphosphorine of the formula I and process of making said compound ##STR1## wherein n=1 or 2 and in which R.sup.1 is a monovalent or divalent aromatic radical wherein a Grignard compound R.sup.1 (MgHal).sub.n is reacted with 6-chloro-6H-dibenzo[c,e][1,2] oxaphosphorine.This compound optionally with phenolic antioxidants, provides stabilization in polymers.

Abstract: Process for the preparation of pure propanephosphonic anhydride, which comprises distilling crude, impure propanephosphonic anhydride having an average degree of polymerization of 20 to 200 and containing less than 0.5% by weight of water by heating to 230 to 300.degree. C. under a pressure of 0.1 to 100 mbar, pure propanephosphonic anhydride having an average degree of polymerization of 20 to 60 being obtained.

Abstract: Aryl phosphinites of the formula (I) ##STR1## can be prepared in a simple manner and in high yields by reacting 2,4-di-tert.-butylphenylphosphonous dihalides with alkyl- or arylmagnesium bromides or alkyl- or arylmagnesium chlorides.Aryl phosphinites serve for the preparation of secondary phosphine oxides which are used as starting materials for the preparation of phosphine ligands in catalyst systems.

Abstract: A process for the preparation of aryl phosphonites of the formula V ##STR1## wherein the radicals and n are defined in the disclosure. The invention further relates to a plastic molding composition, in particular a polyolefin molding composition containing aryl phosphonites of the formula V.

Abstract: Aryl esters of phosphonous halides of the formula I ##STR1## in which R' is a phenyl or benzyl radical which bears 1 to 3 substituents, .alpha.-methylbenzyl, .alpha., .alpha.-dimethylbenzyl, naphthyl or a naphthyl radical bearing 1 to 5 substituents, where the substituents are identical or different and are a non-aromatic hydrocarbon radical, an alkoxy radical or alkylthio radical each having 1 to 8 carbon atoms, aryl or aryloxy each having 6 to 10 carbon atoms or halogen having an atomic number from 9 to 35,R.sup.2 is a non-aromatic hydrocarbon radical having 1 to 18 carbon atoms, aryl, arylmethyl, arylethyl or arylisopropyl, where each aryl contains 6 to 10 carbon atoms,R.sup.3 is hydrogen or one of the groups mentioned under R.sup.2, andX is chlorine or bromine.The invention further relates to a process for the preparation of aryl esters of phosphonous halides of the formula I.

Abstract: Diarylphosphinous acid aryl esters are made by the disclosed process. These compounds are useful for stabilizing plastics, in particular polymerization plastics, and hence can be incorporated into a plastic molding composition.

Abstract: The invention relates to fiber composite materials and a process for their preparation.The process comprises impregnating fibers with a molten polysilazane in a first step, converting the polysilazane in the fibers into the non-fusible state in a second step, and heating the impregnated fibers to 800.degree. to 2000.degree. C. in a nitrogen, noble gas or ammonia atmosphere in a third step.

Abstract: The invention relates to a process for the preparation of polymeric chlorosilazanes by reaction of oligomeric silazanes with chlorosilanes under at least 30 bar at 250.degree. to 400.degree. C.

Abstract: The invention relates to a process for obtaining phosphorus acid-bis(2,4-di-tert-butylphenyl) ester halides in which a phosphorus acid-2,4-di-tert-butylphenyl ester dihalide is heated in the presence of a catalyst containing nitrogen or phosphorus, or both, to 130.degree. C. to 280.degree. C. and the phosphorus trihalide produced by disproportionation is removed from the reaction mixture.

Abstract: The invention relates to novel polymeric hydridochlorosilazanes, to their preparation, to their processing to form ceramic materials containing silicon nitride, and to said materials themselves. The polymeric hydridochlorosilazanes are prepared by reacting oligohydridoorganosilazanes of the general formula (R.sup.1 SiHNH).sub.n, in which n is about 3 to about 12, with at least one of the chlorosilanes R.sup.2 SiHCl.sub.2, R.sup.3 SiCl.sub.3, Cl.sub.2 R.sup.4 Si--CH.sub.2 CH.sub.2 --SiR.sup.4 Cl.sub.2 or Cl.sub.3 Si--CH.sub.2 CH.sub.2 --SiR.sup.5 Cl.sub.2 at 30.degree. C. to 300.degree. C., where the radicals independently of one another have the following meanings:R.sup.1 =a C.sub.1 -C.sub.6 alkyl or C.sub.2 -C.sub.6 alkenyl group,R.sup.2 =a C.sub.2 -C.sub.6 alkenyl group if R.sup.2 SiHCl.sub.2 is reacted with the oligosilazanes by itself, orR.sup.2 =a C.sub.1 -C.sub.6 alkyl or C.sub.2 -C.sub.6 alkenyl group if R.sup.2 SiHCl.sub.2 is reacted with the oligosilazanes as a mixture with other chlorosilanes, andR.

Abstract: The invention relates to novel silazane polymers containing SiCl groups, to their preparation, to their conversion into silicon nitride-containing ceramic material, and to this material itself. In order to prepare the silazane polymers containing SiCl groups, .alpha.,.omega.-chlorosilazanes of the formula I ##STR1## in which m has a value of from 1 to 12 and --(Si) is a silyl radical of the formula --SiHR.sup.1 Cl, --SiR.sup.2 R.sup.3 Cl, --SiR.sup.4 Cl.sub.2, --SiR.sup.5 Cl-CH.sub.2 CH.sub.2 -SiR.sup.5 Cl.sub.2 or --SiCl.sub.2 -CH.sub.2 CH.sub.2 -SiR.sup.6 Cl.sub.2, and R is C.sub.1 -C.sub.6 -alkyl or C.sub.2 -C.sub.6 -alkenyl and, independently of one another, R.sup.1 -R.sup.6 are H, C.sub.1 -C.sub.6 -alkyl or C.sub.2 -C.sub.6 -alkenyl, to a temperature of from 100.degree. C. to 400.degree. C.The silazane polymers according to the invention containing in SiCl groups can be reacted with ammonia to give polysilazanes, which can themselves be pyrolyzed to give silicon nitride-containing ceramic materials.

Abstract: The invention relates to a process for the production of a ceramic/fiber composite.The process comprises impregnating fibers with a molten polysilazane in a first step, converting the polysilazane in the fibers into the infusible state in a second step and, in a third step, heating the impregnated fibers to 800.degree. to 2000.degree. C. in an atmosphere of nitrogen, noble gas, or ammonia.

Abstract: The invention relates to a novel sinterable ceramic powder, to its preparation and to its further processing to give a silicon nitride ceramic, and to this material itself and its use. The sinterable ceramic powder is produced by melting a polysilazane or dissolving it in an organic solvent, suspending a powdered sinter aid in this melt or solution, then pyrolyzing the melt, or the residue obtained after evaporation of the solvent, at 500.degree. to 1600.degree. C. in a protective gas atmosphere, the polysilazane eitherA) being obtainable by reacting at least one of the oligosilazanes of the formula (I) ##STR1## in which a, b, c and d are the mole fractions of the respective structural units and where 0.ltoreq.a.ltoreq.1, 0.ltoreq.b.ltoreq.1, 0.ltoreq.c.ltoreq.0.7, 0.ltoreq.d.ltoreq.0.7, 0.3.ltoreq.a+b, c+d.ltoreq.0.7 and n is approximately 2 to approximately 12, with at least one of the chlorosilanes R.sup.6 R.sup.7 SiCl.sub.2, R.sup.8 SiCl.sub.3, Cl.sub.2 R.sup.9 Si--CH.sub.2 CH.sub.2 --SiR.sup.9 Cl.sub.

Abstract: Acylaminomethanephosphonic acids are useful intermediates for the preparation of the herbicide N-phosphonemethylglycine and its salts.According to the invention, acylaminomethanephosphonic acids of the formula (I)R.sup.1 --CO--NHCH.sub.2 P(.dbd.O) (OH).sub.2 (I)in which R.sup.1 is H, C.sub.1 -C.sub.6 -alkyl, benzyl or optionally substituted phenyl, can be prepared in a process which can be employed industrially, which comprises the reaction of the compound of the formula R.sup.1 --CO-NH--CH.sub.2 OH with P.sub.2 O.sub.3 and then hydrolysis with water.

Abstract: The invention relates to a high-strength ceramic composite, in particular made from silicon nitride, a process for its preparation and its use. The process comprises impregnating an open-pore matrix with a molten polysilazane in a first step and, in a second step, heating the impregnated matrix to 800.degree. to 2500.degree. C. under a blanketing gas, such as nitrogen or a noble gas, or to 800.degree. to 1500.degree. C. under a gas containing ammonia. The high-strength ceramic composite prepared can be used as a component to be subjected to high thermal, mechanical or corrosive stress.

Abstract: The invention 1204 to a process for the preparation of .alpha., .omega.-chlorosilazanes which comprises reacting an oligohydridoorganylsilazane of the formula [--RSiH--NH--].sub.n in which n is from about 3 to about 12 with at least one of the chlorosilanes R.sup.1 HSiCl.sub.2, R.sup.2 R.sup.3 SiCl.sub.2, R.sup.4 SiCl.sub.3, Cl.sub.2 R.sup.5 SiCl.sub.2 CH.sub.2 SiR.sup.5 Cl.sub.2 and Cl.sub.3 SiCH.sub.2 CH.sub.2 SiR.sup.6 Cl.sub.2 where R is C.sub.1 -C.sub.6 -alkyl or C.sub.2 -C.sub.6 -alkenyl and,independently of one another, R.sup.1 -R.sup.6 are H, C.sub.1 -C.sub.6 alkyl, or C.sub.2 -C.sub.6 -alkenyl, at from -20.degree. C. to +50.degree. C. In addition, the invention relates to the novel .alpha., .omega.-chlorosilazanes obtainable by this process.