TWO-STEP AND ONE-POT PROCESSES FOR PREPARATION OF ALIPHATIC DIISOCYANATES

摘要

The present invention relates to using a two-step (thermolysis) or one-pot process to prepare aliphatic diisocyanates from aliphatic diamines and diaryl carbonates. Polyisocyanates can also be prepared from polyamines and diaryl carbonates. The present synthetic processes do not apply phosgene or highly toxic reagents and chloro-solvents during the entire procedure.

主权项

1. A process for preparing aliphatic biscarbamates, the process comprising a step of reacting at least one aliphatic diamine or aliphatic polyamine with diaryl carbonate in a first solvent having low polarity to produce at least one biscarbamate or polycarbamate, the reaction optionally using a non-metal catalyst, and the first solvent having low polarity being ether or alcohol ether.