Solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on αβ-unsaturated carbonyl compounds
The reaction of phenyllithium with E-cinnamaldehyde is extremely sensitive to the reaction conditions and surprising changes in the product distribution were observed upon changes in the solvent, concentrations, duration or temperature of the reaction. For these reasons the above mentioned reaction...
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2005
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14220067_v6_n1-2_p97_Nudelman http://hdl.handle.net/20.500.12110/paper_14220067_v6_n1-2_p97_Nudelman |
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paper:paper_14220067_v6_n1-2_p97_Nudelman2023-06-08T16:13:49Z Solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on αβ-unsaturated carbonyl compounds Aggregates Chalcones Cinnamaldehyde Phenyllithium Tandem reactions carbonyl derivative chalcone derivative cinnamaldehyde lithium derivative phenyllithium unclassified drug addition reaction article concentration response lithiation reaction analysis substitution reaction synthesis temperature sensitivity The reaction of phenyllithium with E-cinnamaldehyde is extremely sensitive to the reaction conditions and surprising changes in the product distribution were observed upon changes in the solvent, concentrations, duration or temperature of the reaction. For these reasons the above mentioned reaction was considered an appropriate model to examine solvent and aggregation effects of PhLi. On the other hand, when two or trhee equiv of phenyllithium are used, instead of one, the reaction transforms into a surprising tandem addition-lithiation-β-alkylation sequence, that can be successfully applied to the synthesis of substituted dihydrochalcones. The observed effects upon changes in the reaction conditions, as well as the effects of additives that modify the PhLi dimer-monomer equilibrium are consistent with a reaction pathway in which dimeric phenyl lithium attacks to the E-cinnamaldehyde without previous deaggregation. Usually, monomers are found to be more reactive than dimers, but, in this reaction the opposite effect is observed, and the tandem reaction spectacularly decreases with the (PhLi) 2 concentration. © 2005 by MDPI. 2005 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14220067_v6_n1-2_p97_Nudelman http://hdl.handle.net/20.500.12110/paper_14220067_v6_n1-2_p97_Nudelman |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Aggregates Chalcones Cinnamaldehyde Phenyllithium Tandem reactions carbonyl derivative chalcone derivative cinnamaldehyde lithium derivative phenyllithium unclassified drug addition reaction article concentration response lithiation reaction analysis substitution reaction synthesis temperature sensitivity |
| spellingShingle |
Aggregates Chalcones Cinnamaldehyde Phenyllithium Tandem reactions carbonyl derivative chalcone derivative cinnamaldehyde lithium derivative phenyllithium unclassified drug addition reaction article concentration response lithiation reaction analysis substitution reaction synthesis temperature sensitivity Solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on αβ-unsaturated carbonyl compounds |
| topic_facet |
Aggregates Chalcones Cinnamaldehyde Phenyllithium Tandem reactions carbonyl derivative chalcone derivative cinnamaldehyde lithium derivative phenyllithium unclassified drug addition reaction article concentration response lithiation reaction analysis substitution reaction synthesis temperature sensitivity |
| description |
The reaction of phenyllithium with E-cinnamaldehyde is extremely sensitive to the reaction conditions and surprising changes in the product distribution were observed upon changes in the solvent, concentrations, duration or temperature of the reaction. For these reasons the above mentioned reaction was considered an appropriate model to examine solvent and aggregation effects of PhLi. On the other hand, when two or trhee equiv of phenyllithium are used, instead of one, the reaction transforms into a surprising tandem addition-lithiation-β-alkylation sequence, that can be successfully applied to the synthesis of substituted dihydrochalcones. The observed effects upon changes in the reaction conditions, as well as the effects of additives that modify the PhLi dimer-monomer equilibrium are consistent with a reaction pathway in which dimeric phenyl lithium attacks to the E-cinnamaldehyde without previous deaggregation. Usually, monomers are found to be more reactive than dimers, but, in this reaction the opposite effect is observed, and the tandem reaction spectacularly decreases with the (PhLi) 2 concentration. © 2005 by MDPI. |
| title |
Solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on αβ-unsaturated carbonyl compounds |
| title_short |
Solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on αβ-unsaturated carbonyl compounds |
| title_full |
Solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on αβ-unsaturated carbonyl compounds |
| title_fullStr |
Solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on αβ-unsaturated carbonyl compounds |
| title_full_unstemmed |
Solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on αβ-unsaturated carbonyl compounds |
| title_sort |
solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on αβ-unsaturated carbonyl compounds |
| publishDate |
2005 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14220067_v6_n1-2_p97_Nudelman http://hdl.handle.net/20.500.12110/paper_14220067_v6_n1-2_p97_Nudelman |
| _version_ |
1768542471023755264 |