Stereoselective, solvent free, highly efficient synthesis of aldo- and keto-N-acylhydrazones applying grindstone chemistry
作者:José Maurício dos Santos Filho、Savio Moita Pinheiro
DOI:10.1039/c7gc00730b
日期:——
A mild and efficientsynthesis of N-acylhydrazones has been developed, applying a simple grindstone procedure, leading to a library of 51 examples exhibiting a broad variety of structural features, 21 of them described for the first time in this paper. This methodology works without any organic solvent under the catalysis of acetic acid at room temperature, promotes the formation of essentially pure
A Convenient Synthesis of Substituted Pyrazolidines and Azaproline Derivatives through Highly Regio- and Diastereoselective Reduction of 2-Pyrazolines
作者:Jesús M. de los Santos、Yago López、Domitila Aparicio、Francisco Palacios
DOI:10.1021/jo702050t
日期:2008.1.1
The synthesis of substituted N-acetyl- and N-aroyl-2-pyrazolines via intramolecular Michael addition of α,β-unsaturated hydrazones generated through olefination of phosphinyl and phosphonyl hydrazones with carbonyl compounds is reported. The regioselective reduction of the C−N double bond in these 2-pyrazolines using Superhydride (Et3BHLi) gives pirazolidine derivatives with excellent levels of ci