Methods for the production of L-glufosinate (also known as phosphinothricin or (S)-2-amino-4-(hydroxy(methyl)phosphonoyl)butanoic acid) ammonium salt are provided. The methods comprise a refined multi-step process. The first step involves the oxidative deamination of D-glufosinate to PPO (2-oxo-4-(hydroxy(methyl)phosphinoyl)butyric acid). The second step involves the specific amination of PPO to L-glufosinate, using an amine group from one or more amine donors. The third step involves the enrichment of the desired enantiomer in the yield by conversion of the obtained side product to the desired final product as well. By addition of the third refinement step, the proportion of the D-glufosinate present in a mixture of L-glufosinate and D-glufosinate can substantially be converted to the desired L-glufosinate ammonium salt.

Cell binding agent-drug conjugates comprising phosphinate-based charged linkers and methods of using such linkers and conjugates are provided.

Cell binding agent-drug conjugates comprising phosphinate-based charged linkers and methods of using such linkers and conjugates are provided.

Cell binding agent-drug conjugates comprising phosphinate-based charged linkers and methods of using such linkers and conjugates are provided.

Mixtures of at least one dialkylphosphinic acid with at least one other dialkylphosphinic acid that is different therefrom, method for production thereof, and use thereof. The invention relates to a mixture of at least one dialkylphosphinic acid of the formula (I) ##STR00001##
in which R.sup.1, R.sup.2 are the same or different and are each C.sub.1-C.sub.18-alkyl, C.sub.2-C.sub.18-alkenyl, C.sub.6-C.sub.18-aryl, C.sub.7-C.sub.18-alkylaryl,
with at least one different dialkylphosphinic acid of the formula (II) ##STR00002##
in which R.sup.3, R.sup.4 are the same or different and are each C.sub.1-C.sub.18-alkyl, C.sub.2-C.sub.18-alkenyl, C.sub.6-C.sub.18-aryl and/or C.sub.7-C.sub.18-alkylaryl,
with the proviso that at least one of the R.sup.3 and R.sup.4 radicals is different than R.sup.1 and R.sup.2.

Compositions and methods for isolating L-glufosinate from a composition comprising L-glufosinate and glutamate are provided. The method comprises converting the glutamate to pyroglutamate followed by the isolation of L-glufosinate from the pyroglutamate and other components of the composition to obtain substantially purified L-glufosinate. The composition comprising L-glufosinate and glutamate is subjected to an elevated temperature for a sufficient time to allow for the conversion of glutamate to pyroglutamate, followed by the isolation of L-glufosinate from the pyroglutamate and other components of the composition to obtain substantially purified L-glufosinate. The glutamate alternatively may be converted to pyroglutamate by enzymatic conversion. The purified L-glufosinate is present in a final composition at a concentration of 90% or greater of the sum of L-glufosinate, glutamate, and pyroglutamate. In some embodiments, a portion of the glutamate in the starting composition may be separated from the L-glufosinate using a crystallization step. Solid forms of L-glufosinate materials, including crystalline L-glufosinate ammonium, are also described.

The present invention relates to an improved method for preparing acrolein cyanohydrins from hydrocyanic acid and the corresponding acroleins. The method is characterized in that the acrolein cyanohydrins obtained have a very low hydrocyanic acid content or are free of hydrocyanic acid and are therefore particularly well suited as intermediates for the synthesis of glufosinates.

Disclosed are a hybrid dialkylphosphinic acid salt, and a preparation method therefor and an application thereof. The hybrid dialkylphosphinic acid salt is at least one of compounds represented by Formula (I). The hybrid dialkylphosphinic acid salt of Formula (I) provided herein features a low required loading level, high flame retardant efficiency for various polymers, and high economic efficiency. The present invention overcomes the disadvantage of low flame retardant efficiency of diethylphosphinate in polymers as well as high volatility and low flame retardant efficiency for polyesters of diisobutylphosphinate. The hybrid dialkylphosphinate salt of Formula (I) can be widely applied to flame retardant polymers which require high-temperature processing.

Disclosed are a hybrid dialkylphosphinate salt, a method for preparing same, and use thereof. The hybrid dialkylphosphinate salt is selected from at least one of the compounds represented by Formula (I). The hybrid dialkylphosphinate salt of Formula (I) provided herein features a low required loading level, high flame retardant efficiency for various polymers, and good thermal stability. The present invention overcomes the disadvantage of low flame retardant efficiency of diethylphosphinate in polymers as well as low thermal stability and large dust of dipropylphosphinate. The hybrid dialkylphosphinate salt of Formula (I) can be widely applied to flame retardant polymers which require high-temperature processing.

Sustainably produced dialkylphosphinic salts The invention provides a process for producing dialkylphosphinic salts of the formula (I),

##STR00001## in which a and b may be the same or different and are each independently 1 to 9, and where the carbon chains may be linear, branched or cyclic, and M is Mg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Li, Na, K and/or a protonated nitrogen base and m is 1 to 4, characterized in that the process comprises: feeding a substream of renewable raw materials and/or recycled raw materials into a main stream of conventional raw materials originated from petroleum; converting said renewable raw material and/or recycled raw materials to ethylene together with said conventional raw materials; reacting the resultant ethylene stream with derivatives of hypophosphorous acid to give a derivative of the dialkylphosphinic acid; and reacting said derivative of the dialkylphosphinic acid with a metal salt to give dialkylphosphinic salts of the formula (I), wherein the renewable raw materials are tall oil, tung oil, wood tar, creosote, or vegetable oils such as palm oil, soya oil, rapeseed oil, sunflower oil, palm kernel oil, cottonseed oil, peanut oil, maize kernel oil, coconut oil, olive oil, sesame oil, linseed oil and/or safflower oil, wherein said recycled raw materials are selected from food wastes, residues or wastes from food production, papermaking or pulp processing, and any other materials of recycled origin, and the ratio of said mainstream of conventional raw material to said substream of renewable raw materials and/or recycled raw materials is 10.sup.9:1 to 1:10.sup.6.