Novel and efficient aqueous phase synthesis of N-substituted azepines via tandem Michael addition and cyclization in the presence of β-cyclodextrin
作者:K. Ramesh、S. Narayana Murthy、Y.V.D. Nageswar
DOI:10.1016/j.tetlet.2011.02.082
日期:2011.5
N-substituted azepines were synthesized for the first time in water under neutral conditions by the reaction of aromatic amines, dimethyl/diethyl acetylene dicarboxylate, 2,5-dimethoxytetrahydrofuran mediated by β-cyclodextrin in high yields. β-Cyclodextrin can be recovered and reused with just a small loss of catalytic activity.
Polyethylene Glycol (PEG-400) as an Efficient and Recyclable Reaction Medium for the One-Pot Synthesis of N-Substituted Azepines under Catalyst-Free Conditions
Polyethyleneglycol (PEG) was found to be an inexpensive nontoxic and effective medium for the one-pot synthesis of N-substituted azepines under catalyst-free conditions in excellent yields. Environmental acceptability, low cost, high yields, and recyclability of the PEG are the important features of this protocol. anilines - dialkylacetylene dicarboxylates - 2,5-dimethoxytetrahydrofuran - N-substituted