387354-11-2

Upstream product

• 768-33-2 phenyldimethylsilyl chloride 
• 387354-09-8 4-iodo-3-methyl-1-phenyl-1H-pyrazole 
• 263914-93-8 4-(dimethyl(phenyl)silyl)but-3-yn-2-one 
• 100-63-0 phenylhydrazine 
• 59-88-1 phenylhydrazine hydrochloride 
• 23183-95-1 1-dimethylphenylsilyl-2-trimethylsilylacetylene 
• 460095-39-0 4-dimethylphenylsilyl-3-butyn-2-one phenylhydrazone 

Relevant academic research and scientific papers

Regiospecific synthesis of 5-silyl azoles

5-Silylisoxazoles bearing other silyl groups different to the more usual trimethylsilyl have been prepared by condensation of silylalkynones with hydroxylamine hydrochloride. The reaction with hydrazines is more complex and leads to 5-silylpyrazoles or the corresponding hydrazones, which can be cyclized by reaction with electrophiles. This has allowed us to synthesize 5-silylpyrazoles functionalized at C-4 by groups impossible to introduce by electrophilic substitution of the pyrazole nucleus.

Synthesis and reactions of silylated and stannylated 1,2-azoles

Silicon or tin 4-metalated pyrazoles and isoxazoles are synthesized by silyl- or stannylcupration from 4-haloazoles. On the other hand, 5-metalated pyrazoles are prepared by reaction of 5-un-substituted pyrazoles with LDA and subsequent treatment with chlorosilanes and chlorostannanes. Furthermore, starting from 5-unsubstituted 4-halopyrazoles and applying both methodologies, 4,5-dimetalated pyrazoles bearing silyl groups different from trimethylsilyl or tributylstannyl groups are obtained. Some regioselective ipso-substitutions are also studied.