Synthesis, Molecular Structure of Diethyl Phenylenebis(Methylene)Dicarbamates and FTIR Spectroscopy Molecular Recognition Study with Benzenediols
摘要:
The synthesis, density functional theory (DFT) molecular structure and Fourier transform infrared spectroscopy (FTIR) molecular recognition study of diethyl phenylenebis(methylene) dicarbamates with 1,2- and 1,3-benzenediols is described. The formation of the complexes was confirmed by the shift of the O-H stretching bands in the IR spectra of the complexes compared with the IR spectra of the noncomplexed benzenediols.
Synthesis, Molecular Structure of Diethyl Phenylenebis(Methylene)Dicarbamates and FTIR Spectroscopy Molecular Recognition Study with Benzenediols
摘要:
The synthesis, density functional theory (DFT) molecular structure and Fourier transform infrared spectroscopy (FTIR) molecular recognition study of diethyl phenylenebis(methylene) dicarbamates with 1,2- and 1,3-benzenediols is described. The formation of the complexes was confirmed by the shift of the O-H stretching bands in the IR spectra of the complexes compared with the IR spectra of the noncomplexed benzenediols.
N-Substituted carbamate synthesis using urea as carbonyl source over TiO<sub>2</sub>–Cr<sub>2</sub>O<sub>3</sub>/SiO<sub>2</sub> catalyst
作者:Peixue Wang、Yubo Ma、Shimin Liu、Feng Zhou、Benqun Yang、Youquan Deng
DOI:10.1039/c5gc01007a
日期:——
The synthesis of N-substituted carbamates from amines, urea and alcohols over a TiO2–Cr2O3/SiO2 catalyst.
从胺、尿素和醇在TiO2–Cr2O3/SiO2催化剂上合成N-取代的碳酸酯。
METHOD FOR TREATMENT OF ISOCYANATE RESIDUE, AND METHOD FOR TREATMENT OF CARBONATE
申请人:Shimokawatoko Yoshiki
公开号:US20120271067A1
公开(公告)日:2012-10-25
A method for treating an isocyanate residue, which comprises carrying out a thermal decomposition reaction of a carbamate that is produced by the reaction among an amine, urea and/or an N-unsubstituted carbamic acid ester and an alcohol to produce a decomposition solution, separating an isocyanate and the alcohol from the decomposition solution to produce the isocyanate residue, and bringing the isocyanate residue into contact with high-pressure/high-temperature water to decompose the isocyanate residue into an amine; and a method for treating a carbonate, which comprises bringing the carbonate into contact with high-pressure/high-temperature water to decompose the carbonate into an alcohol.
Die Erfindung betrifft ein verbessertes Verfahren zur Herstellung von Polyisocyanaten durch thermische Spaltung der entsprechenden Carbamate, bei welchem man die Umsetzung in Gegenwart von stabilisierend wirkenden Hilfsmitteln, ausgewählt aus der Gruppe bestehend aus Chlorwasserstoff, anorganischen und organischen Säurechloriden, alkylierend wirkenden Verbindungen und Organozinn-IV-chloriden durchführt.