Efficient Microwave-Assisted Solvent-Free Synthesis of N-Substituted Aldimines

Abstract

Neat non-volatile amines react with various aromatic aldehydes in the absence of any catalyst, solid support, or solvent, to give imines after a reaction time of eight minutes under microwave irradiation by a clean and very efficient process (yields: 75-100%). In the case of volatile amine, methylamine, 1,3-dimethylurea dispersed on montmorillonite K10 is used as an amine precursor to prepare the corresponding imines.

Key words

solvent-free reactions - microwave activation - N-substituted imines - ureas

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Compare to a commercial product: CAS number 6852-56-8.

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Beilsteins Handbuch der Organischen Chemie; E IV, Vol. 7: 518; compare to a commercial product, CAS number 622-29-7.