Patent classifications
C07C319/28
Mixture Containing Methionine Hydroxy Analog and Oligomer Thereof, and Preparation Method Therefor
Provided in the present disclosure is a mixture, comprising 86-89 wt % of a methionine hydroxy analog and an oligomer thereof, more than 99.95 wt % being a monomer, dimer and trimer, and the ratio of monomer:dimer:trimer by weight being 77-80:18.5-19.5:3-4; 9.2-13.5 wt % of water; and less than 0.5 wt % of ammonium sulfate and ammonium bisulfate. The viscosity of the mixture at 10° C. is lower than 200 mPa.Math.s. Further provided is a method for processing a mixture containing a methionine hydroxy analog and an oligomer thereof.
PROCESS FOR THE CO-PRODUCTION OF METHYL MERCAPTAN AND OF DIMETHYL DISULFIDE FROM CARBON OXIDES
The invention relates to a process for the co-production of methyl mercaptan and of dimethyl disulfide, comprising the following successive steps: a) reaction of at least one carbon oxide in the presence of hydrogen sulfide (H.sub.2S) and hydrogen to form a stream (M) comprising methyl mercaptan, water, and possibly unreacted hydrogen sulfide, b) purification of the stream (M) to obtain a stream (N) enriched in methyl mercaptan and a stream containing the uncondensable compounds (M.sub.uncond), c) optional recycling of the stream of uncondensable compounds (M.sub.uncond) obtained from step b) into step a), d) recovery of a first portion of the stream (N) including methyl mercaptan purified in step b), e) oxidation with sulfur of the second portion of the stream (N) of methyl mercaptan, to form a stream (O) comprising dimethyl disulfide, hydrogen sulfide, and possibly unreacted methyl mercaptan, f) purification of the stream (O) to separate, on the one hand, the enriched dimethyl disulfide and, on the other hand, the hydrogen sulfide and possibly the methyl mercaptan that has not reacted in step e), g) recycling of the hydrogen sulfide and possibly of the methyl mercaptan isolated in step f) into the stream (M) obtained from step a), h) recovery of the dimethyl disulfide isolated in step f).
PROCESS FOR THE CO-PRODUCTION OF METHYL MERCAPTAN AND OF DIMETHYL DISULFIDE FROM CARBON OXIDES
The invention relates to a process for the co-production of methyl mercaptan and of dimethyl disulfide, comprising the following successive steps: a) reaction of at least one carbon oxide in the presence of hydrogen sulfide (H.sub.2S) and hydrogen to form a stream (M) comprising methyl mercaptan, water, and possibly unreacted hydrogen sulfide, b) purification of the stream (M) to obtain a stream (N) enriched in methyl mercaptan and a stream containing the uncondensable compounds (M.sub.uncond), c) optional recycling of the stream of uncondensable compounds (M.sub.uncond) obtained from step b) into step a), d) recovery of a first portion of the stream (N) including methyl mercaptan purified in step b), e) oxidation with sulfur of the second portion of the stream (N) of methyl mercaptan, to form a stream (O) comprising dimethyl disulfide, hydrogen sulfide, and possibly unreacted methyl mercaptan, f) purification of the stream (O) to separate, on the one hand, the enriched dimethyl disulfide and, on the other hand, the hydrogen sulfide and possibly the methyl mercaptan that has not reacted in step e), g) recycling of the hydrogen sulfide and possibly of the methyl mercaptan isolated in step f) into the stream (M) obtained from step a), h) recovery of the dimethyl disulfide isolated in step f).
PROCESS FOR THE CO-PRODUCTION OF ALKYL MERCAPTAN AND DIALKYL DISULFIDE FROM ALCOHOL
The invention relates to a process for the co-production of alkyl mercaptan and of dialkyl disulfide, comprising the following successive steps: a) reaction of a C.sub.1-C.sub.4 alcohol in the presence of hydrogen sulfide (H.sub.2S) to form a stream (M) comprising an alkyl mercaptan, water, and possibly unreacted hydrogen sulfide, b) purification of the stream (M) to obtain a stream (N) enriched in alkyl mercaptan, c) recovery of a first portion of the stream (N) including the alkyl mercaptan purified in step b), d) oxidation with sulfur of the second portion of the stream (N) of alkyl mercaptan, to form a stream (O) comprising a dialkyl disulfide, hydrogen sulfide, and possibly unreacted alkyl mercaptan, e) purification of the stream (O) to separate, on the one hand, the enriched dialkyl disulfide and, on the other hand, the hydrogen sulfide and possibly the alkyl mercaptan that has not reacted in step d), f) recycling of the hydrogen sulfide and possibly of the alkyl mercaptan isolated in step e) into the stream (M) obtained from step a), g) recovery of the dialkyl disulfide isolated in step e).
PROCESS FOR THE CO-PRODUCTION OF ALKYL MERCAPTAN AND DIALKYL DISULFIDE FROM ALCOHOL
The invention relates to a process for the co-production of alkyl mercaptan and of dialkyl disulfide, comprising the following successive steps: a) reaction of a C.sub.1-C.sub.4 alcohol in the presence of hydrogen sulfide (H.sub.2S) to form a stream (M) comprising an alkyl mercaptan, water, and possibly unreacted hydrogen sulfide, b) purification of the stream (M) to obtain a stream (N) enriched in alkyl mercaptan, c) recovery of a first portion of the stream (N) including the alkyl mercaptan purified in step b), d) oxidation with sulfur of the second portion of the stream (N) of alkyl mercaptan, to form a stream (O) comprising a dialkyl disulfide, hydrogen sulfide, and possibly unreacted alkyl mercaptan, e) purification of the stream (O) to separate, on the one hand, the enriched dialkyl disulfide and, on the other hand, the hydrogen sulfide and possibly the alkyl mercaptan that has not reacted in step d), f) recycling of the hydrogen sulfide and possibly of the alkyl mercaptan isolated in step e) into the stream (M) obtained from step a), g) recovery of the dialkyl disulfide isolated in step e).
PROCESS FOR THE CO-PRODUCTION OF ALKYL MERCAPTAN AND DIALKYL DISULFIDE FROM ALCOHOL
The invention relates to a process for the co-production of alkyl mercaptan and of dialkyl disulfide, comprising the following successive steps: a) reaction of a C.sub.1-C.sub.4 alcohol in the presence of hydrogen sulfide (H.sub.2S) to form a stream (M) comprising an alkyl mercaptan, water, and possibly unreacted hydrogen sulfide, b) purification of the stream (M) to obtain a stream (N) enriched in alkyl mercaptan, c) recovery of a first portion of the stream (N) including the alkyl mercaptan purified in step b), d) oxidation with sulfur of the second portion of the stream (N) of alkyl mercaptan, to form a stream (O) comprising a dialkyl disulfide, hydrogen sulfide, and possibly unreacted alkyl mercaptan, e) purification of the stream (O) to separate, on the one hand, the enriched dialkyl disulfide and, on the other hand, the hydrogen sulfide and possibly the alkyl mercaptan that has not reacted in step d), f) recycling of the hydrogen sulfide and possibly of the alkyl mercaptan isolated in step e) into the stream (M) obtained from step a), g) recovery of the dialkyl disulfide isolated in step e).
PLEUROMUTILIN 2-[(DIPHENYLMETHYL)THIO]ACETIC ACID ESTER WITH ANTI-DRUG RESISTANT BACTERIA ACTIVITY AND A METHOD OF PREPARING THE SAME
A compound with anti-drug resistant bacteria activity having the formula (I):
##STR00001##
is disclosed. The methods of preparing the compound of formula (I) are also disclosed.
PLEUROMUTILIN 2-[(DIPHENYLMETHYL)THIO]ACETIC ACID ESTER WITH ANTI-DRUG RESISTANT BACTERIA ACTIVITY AND A METHOD OF PREPARING THE SAME
A compound with anti-drug resistant bacteria activity having the formula (I):
##STR00001##
is disclosed. The methods of preparing the compound of formula (I) are also disclosed.
RREPARATION METHOD OF 3-MERCAPTOPROPIONIC ACID
The present disclosure relates to the field of synthesis of mercapto compounds, and in particular, to a preparation method of 3-mercaptopropionic acid. The preparation method provided by the present disclosure comprises the steps of: mixing sodium acrylate with sodium hydrosulfide or sodium sulfide for reacting; adding sodium sulfide (or adding sodium sulfide and sulfur powder) for further reacting; crystallizing, and acidifying with an acid to obtain a solution of 3-mercaptopropionic acid. According to the preparation method provided by the present disclosure, the raw materials are inexpensive, the product 3-mercaptopropionic acid can be obtained with a high yield and high purity, moreover, and solid waste and solvent(s) can be separated and recovered; sodium salt can be used as an industrial product after crystallization; the solvent(s) can be recovered and recycled by distillation; and disposal of three wastes is simple.
RREPARATION METHOD OF 3-MERCAPTOPROPIONIC ACID
The present disclosure relates to the field of synthesis of mercapto compounds, and in particular, to a preparation method of 3-mercaptopropionic acid. The preparation method provided by the present disclosure comprises the steps of: mixing sodium acrylate with sodium hydrosulfide or sodium sulfide for reacting; adding sodium sulfide (or adding sodium sulfide and sulfur powder) for further reacting; crystallizing, and acidifying with an acid to obtain a solution of 3-mercaptopropionic acid. According to the preparation method provided by the present disclosure, the raw materials are inexpensive, the product 3-mercaptopropionic acid can be obtained with a high yield and high purity, moreover, and solid waste and solvent(s) can be separated and recovered; sodium salt can be used as an industrial product after crystallization; the solvent(s) can be recovered and recycled by distillation; and disposal of three wastes is simple.