Cyclization of Propargylic Amides: Mild Access to Oxazole Derivatives
作者:Jan P. Weyrauch、A. Stephen K. Hashmi、Andreas Schuster、Tobias Hengst、Stefanie Schetter、Anna Littmann、Matthias Rudolph、Melissa Hamzic、Jorge Visus、Frank Rominger、Wolfgang Frey、Jan W. Bats
DOI:10.1002/chem.200902472
日期:2010.1.18
the oxazole synthesis were developed and chelate ligands can be obtained. The use of Barluenga’s reagent offers a new and mild access to the synthetically valuable iodoalkylideneoxazoles from propargylicamides, this reagent being superior to other sources of halogens.
Remarkably, cis-endo-norbornene 21 performed comparably to benzene-core derivatives. Conformational analysis reveals a preference for compounds 1 and 21 to adopt folded conformations. These results highlight the potential of norbornenes as a new class of aliphatic scaffolds for the synthesis of anti-adhesion compounds.
Halide binding and self-assembling behavior of Triazole-based acyclic and cyclic molecules
作者:V. Haridas、Srikanta Sahu、P. Venugopalan
DOI:10.1016/j.tet.2010.11.078
日期:2011.1
The present study demonstrates the use of triazole moiety in designing molecules endowed with the ability for self-assembly and molecular recognition. The receptors 7a and 9a having open structures bind to fluoride ion with good affinity. Various cyclophanes with 19-, 20-, 21-, 38-, and 40-membered rings containing triazole units were designed and synthesized. X-ray crystal structure of macrocycle
A cesium carbonate promoted, transition metal and halogen‐free 5‐exo‐dig type cyclization reaction for the synthesis of oxazoles and imidazoles has been developed.