reagent 2,4,6-tris[(4-dichloroiodo)phenoxy)]-1,3,5-triazine can be applied also for the oxidative synthesis of 1,3,4-oxadiazoles and 1,2,4-thiadiazoles under mild conditions in excellent yields. The recyclability of the 2,4,6-tris[(4-dichloroiodo)phenoxy)]-1,3,5-triazine was possible owing to the facile recovery and reuse of the coproduced 2,4,6-tris(4-iodophenoxy)-1,3,5-triazine from the reaction mixture
Incorporation of α-trifluoromethyl substituted α-amino acids into C-and N-terminal position of peptides and peptide mimetics using multicomponent reactions
作者:K. Burger、K. Mütze、W. Hollweck、B. Koksch
DOI:10.1016/s0040-4020(98)00291-9
日期:1998.5
Methodology for incorporation of α-trifluoromethyl substituted amino acids into the C-and N-terminal position of peptides and peptide mimetics via multicomponent reactions of the Passerini and Ugi type is described.
Alkyl Radical Addition to Aliphatic and Aromatic <i>N</i>-Acylhydrazones Using an Organic Photoredox Catalyst
作者:Stephen T. J. Cullen、Gregory K. Friestad
DOI:10.1021/acs.orglett.9b03053
日期:2019.10.18
biscatecholatosilicates with organocatalyst 4CzIPN, add successfully to both aromatic and aliphatic N-acylhydrazones in the presence of MgCl2. With N-benzoylhydrazones, a simplereductivecleavage of the N–N bond of the hydrazine adduct furnishes the free amine. Synthetic utility is exemplified in a synthetic application toward repaglinide, a clinically important hypoglycemic agent.
A simple and convenient method for the synthesis of 2,5-disubstituted1,3,4-oxadiazoles has been developed. Structurally divergent symmetrical and unsymmetrical 2,5-disubstituted1,3,4-oxadiazoles can be obtained in moderate to high yields via NaOCl-mediated oxidative cyclization of N-acylhydrazones, generated in situ from aliphatic and aromatic hydrazides and aldehydes.
A general, metal‐free, highly enantioselective Brønsted acidcatalyzed [3+2] cycloaddition between hydrazones and alkenes has been developed that affords pyrazolidinederivatives (see scheme). The resulting optically active pyrazolidines can undergo many chemical transformations which allow, for example, the enantioselective synthesis of valuable pyrazolines and 1,3‐diamines.