C07C263/04

METHOD FOR PRODUCING ISOCYANATES

The invention relates to a method for producing an isocyanate, wherein a carbamate or thiolcarbomate is converted, in the presence of a catalyst, with separation of an alcohol or thioalcohol, at a temperature of at least 150 C., to the corresponding isocyanate, wherein a compound of the general formula (X)(Y)(ZH) is used as a catalyst, in particular characterized in that the compound has both a proton donor function and a proton acceptor function. In the catalysts according to the invention, a separable proton is bound to a heteroatom, which is more electronegative than carbon. Said heteroatom is either identical to Z or a component thereof. In the catalysts according to the invention, there is additionally a proton acceptor function which is either identical to X or a component thereof. According to the invention, the proton donator and proton acceptor function are connected to each other by the bridge Y.

MULTISTEP PROCESS FOR THE PREPARATION OF HEXAMETHYLENE DIISOCYANATE, PENTAMETHYLENE DIISOCYANATE OR TOLUENE DIISOCYANATE
20200277254 · 2020-09-03 ·

The present invention relates to a multistep process for the preparation of organic diisocyanates by converting the corresponding diamine precursors, urea and hydroxy compounds into monomeric diurethanes, converting these diurethanes into diurethanes of high boiling hydroxy compounds, and finally cleavage of the latter diurethanes to form the diisocyanates and recover the high boiling hydroxy compounds.

MULTISTEP PROCESS FOR THE PREPARATION OF HEXAMETHYLENE DIISOCYANATE, PENTAMETHYLENE DIISOCYANATE OR TOLUENE DIISOCYANATE
20200277254 · 2020-09-03 ·

The present invention relates to a multistep process for the preparation of organic diisocyanates by converting the corresponding diamine precursors, urea and hydroxy compounds into monomeric diurethanes, converting these diurethanes into diurethanes of high boiling hydroxy compounds, and finally cleavage of the latter diurethanes to form the diisocyanates and recover the high boiling hydroxy compounds.

MULTISTEP PROCESS FOR THE PREPARATION OF HEXAMETHYLENE DIISOCYANATE, PENTAMETHYLENE DIISOCYANATE OR TOLUENE DIISOCYANATE
20200277254 · 2020-09-03 ·

The present invention relates to a multistep process for the preparation of organic diisocyanates by converting the corresponding diamine precursors, urea and hydroxy compounds into monomeric diurethanes, converting these diurethanes into diurethanes of high boiling hydroxy compounds, and finally cleavage of the latter diurethanes to form the diisocyanates and recover the high boiling hydroxy compounds.

MULTISTEP PROCESS FOR THE PREPARATION OF DIISOCYANATES
20200277253 · 2020-09-03 ·

The present invention relates to a process for the preparation of organic diisocyanates by cleaving the corresponding diurethanes into the diisocyanate and a hydroxy compound and separating the diisocyanate from the hydroxy compound by distillation wherein the diisocyanate is obtained as the distillate.

MULTISTEP PROCESS FOR THE PREPARATION OF DIISOCYANATES
20200277253 · 2020-09-03 ·

The present invention relates to a process for the preparation of organic diisocyanates by cleaving the corresponding diurethanes into the diisocyanate and a hydroxy compound and separating the diisocyanate from the hydroxy compound by distillation wherein the diisocyanate is obtained as the distillate.

MULTISTEP PROCESS FOR THE PREPARATION OF DIISOCYANATES
20200277253 · 2020-09-03 ·

The present invention relates to a process for the preparation of organic diisocyanates by cleaving the corresponding diurethanes into the diisocyanate and a hydroxy compound and separating the diisocyanate from the hydroxy compound by distillation wherein the diisocyanate is obtained as the distillate.

ISOCYANATE PRODUCTION METHOD

An isocyanate production method is characterized by having: a carbamation step in which a carbonic acid ester, an inorganic acid salt of an amino acid derivative, and a basic compound are reacted to obtain a reaction mixture containing a carbamic acid ester derived from the carbonic acid ester, a hydroxy compound derived from the carbonic acid ester, and the carbonic acid ester; and a thermal decomposition step in which the carbamic acid ester is subjected to a thermal decomposition reaction to obtain an isocyanate.

ISOCYANATE PRODUCTION METHOD

An isocyanate production method is characterized by having: a carbamation step in which a carbonic acid ester, an inorganic acid salt of an amino acid derivative, and a basic compound are reacted to obtain a reaction mixture containing a carbamic acid ester derived from the carbonic acid ester, a hydroxy compound derived from the carbonic acid ester, and the carbonic acid ester; and a thermal decomposition step in which the carbamic acid ester is subjected to a thermal decomposition reaction to obtain an isocyanate.

ISOCYANATE PRODUCTION METHOD

An isocyanate production method is characterized by having: a carbamation step in which a carbonic acid ester, an inorganic acid salt of an amino acid derivative, and a basic compound are reacted to obtain a reaction mixture containing a carbamic acid ester derived from the carbonic acid ester, a hydroxy compound derived from the carbonic acid ester, and the carbonic acid ester; and a thermal decomposition step in which the carbamic acid ester is subjected to a thermal decomposition reaction to obtain an isocyanate.