Solid Phase Synthesis of Pyridazine Derivatives Using Polymer-Bound Sodium Benzenesulfinate
作者:Yu Chen、Yulin Lam、Soo-Ying Lee
DOI:10.1246/cl.2001.274
日期:2001.3
solid phase synthesis of 3,6-disubstitutedpyridazine derivatives, resulting from the reaction of polymer-bound sodium benzenesulfinate with α-bromoketone substrates followed by condensation with hydrazine, is described. Mild basic conditions for the condensation reaction simultaneously release the desired product from the solid support. The crystal structure of 3,6-bis(p-chlorophenyl)pyridazine is reported
diethylene glycol affords the corresponding pyridazines in high yields with evolution of hydrogen sulfide. The above procedure is generally applicable to the preparation of a wide variety of 3,6-disubstituted pyridazines which are of structural interest and otherwise difficult to prepare.
A simple, mild, and efficient synthesis of symmetric 3,6‐diarylpyridazine derivatives using a green catalytic one‐pot two‐step reaction of aryl methyl ketones, arylglyoxal monohydrates, and hydrazine hydrate was developed. Environmentally benign nature, high atom‐economy, no harmful byproduct, easy workup procedure, no column chromatography steps, and moderate to excellent yields of the products are
Highly selective mono-substitution in Pd-catalyzed cross-coupling reactions of 3,6-dichloropyridazine with organozinc compounds
作者:Dmitriy S. Chekmarev、Alexander E. Stepanov、Alexander N. Kasatkin
DOI:10.1016/j.tetlet.2004.12.124
日期:2005.2
Pd-catalyzedcross-couplingreactions of 3,6-dichloropyridazine (1) with benzyl, aryl, and alkyl organozinc compounds led to selective mono-substitution of one of the chlorine atoms. The subsequent cross-coupling of the resulting monochlorides with RZnCl afforded unsymmetrical 3,6-carbon-disubstituted pyridazines.
The cross-couplingreactions of 3,6-dihalopyridazines with triaryl- or triheteroarylbismuthcompounds were performed under palladium catalysis. The reaction was highly chemoselective, affording functionalized aryl- or heteroarylpyridazinyl chlorides in moderate to good yields.