摘要:
The invention relates to a method for the production of L-carnitine, wherein a chiral β-lactone carnitine precursor is obtained by a [2+2] cycloaddition of ketene with an aldehyde X—CH2—CHO, wherein X is selected from Cl, Br, I and trimethylamine, in the presence of a chiral catalyst.
摘要:
Process for removing hydrogen cyanide from ethanedinitrile by contacting hydrogen cyanide-containing ethanedinitrile with an organic reagent under formation of a covalent bond.
摘要:
The invention relates to a method for the production of L-carnitine, wherein a β-lactone, which is a 4-(halomethyl)oxetane-2-one, is converted into carnitine with trimethylamine (TMA), wherein the β-lactone is not subjected to a basic hydrolysis step before being contacted with the trimethylamine. The invention also relates to a carnitine having a unique impurity profile.
摘要:
The invention relates to a method for the production of L-carnitine, wherein a β-lactone, which is a 4-(halomethyl)oxetane-2-one, is converted into carnitine with trimethylamine (TMA), wherein the β-lactone is not subjected to a basic hydrolysis step before being contacted with the trimethylamine. The invention also relates to a carnitine having a unique impurity profile.
摘要:
The invention relates to a method for the production of L-carnitine, wherein a chiral β-lactone carnitine precursor is obtained by a [2+2] cycloaddition of ketene with an aldehyde X—CH2—CHO, wherein X is selected from Cl, Br, I and trimethylamine, in the presence of a chiral catalyst.
摘要:
Process for removing hydrogen cyanide from ethanedinitrile by contacting hydrogen cyanide-containing ethanedinitrile with an organic reagent under formation of a covalent bond.
摘要:
Ethynylcyclopropane is prepared from (1,1-dimethoxyethyl)cyclopropane by a two-stage elimination of methanol. Ethynylcyclopropane is an intermediate in the synthesis of pharmaceutically active ingredients, for example, antiviral agents.
摘要:
The present invention relates to a process for the selective preparation of acetaldehyde, characterized in that acrolein and one or more ammonium salts dissolved in water are reacted continuously under high pressures and at temperatures of 300-400° C.
摘要:
A method for the production of 6,6,6-trihalo-3,5-dioxohexanic acid esters of formula (I): in addition to the enols thereof and E and Z isomers, wherein X independently represents fluorine, chlorine or bromine and R1 represents alkyl, cycloalkyl, aryl or aralkyl. A method for the production of enol ethers of formula (Ib): and the enols thereof (E and Z isomers) wherein X and R1 have the above-mentioned meanings.
摘要:
A method for the production of 6,6,6-trihalo-3,5-dioxohexanoic acid esters of formula (I): in addition to the enols thereof and E and Z isomers, wherein X independently represents fluorine, chlorine or bromine and R1 represents alkyl, cycloalkyl, aryl or aralkyl. A method for the production of enol ethers of formula (Ib): and the enols thereof (E and Z isomers) wherein X and R1 have the above-mentioned meanings.