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Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Directing group-controlled hydrosilylation: regioselective functionalization of alkyne
Yuuya Kawasaki1, Youhei Ishikawa, Kazunobu Igawa
1Department of Molecular and Material Sciences, Kyushu University, Kasuga, Fukuoka 816-8580, Japan.
Platinum-catalyzed hydrosilylation using a dimethylvinylsilyl (DMVS) directing group achieves high regioselectivity for unsymmetric alkynes. This method enables the synthesis of specific silylalkene isomers and diverse functionalized compounds.
Area of Science:
- Organometallic Chemistry
- Synthetic Organic Chemistry
- Catalysis
Background:
- Hydrosilylation is a key reaction in organic synthesis.
- Controlling regioselectivity in alkyne hydrosilylation remains a challenge.
- Directing groups can influence reaction outcomes.
Purpose of the Study:
- To develop a highly regioselective Pt(0)-catalyzed hydrosilylation of unsymmetric alkynes.
- To investigate the role of the dimethylvinylsilyl (DMVS) group as a directing and accelerating group.
- To explore the synthesis of complex alkenes and functionalized compounds from unsymmetric alkynes.
Main Methods:
- Platinum(0)-catalyzed hydrosilylation reaction.
- Utilizing dimethylvinylsilyl (DMVS) as a directing group on unsymmetric alkynes.
- Subsequent transformation reactions of the resulting silylalkenes.
Main Results:
- Achieved high regioselectivity in the hydrosilylation of unsymmetric alkynes.
- DMVS group directed the formation of a single regioisomer of silylalkenes.
- Observed an accelerating effect of the DMVS group for selective hydrosilylation.
- Synthesized various tri-substituted alkenes and multi-oxy-functionalized compounds with high regioselectivity.
Conclusions:
- The DMVS group is an effective directing and accelerating group for Pt(0)-catalyzed alkyne hydrosilylation.
- This methodology provides a regioselective route to valuable alkene derivatives.
- Enables efficient synthesis of complex organic molecules from simple alkynes.
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