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Updated: May 7, 2025
Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Transition-Metal-Free Thioboration of Terminal Alkynes
Taro Matsuyama1, Hiroshi Ishida1, Chao Wang2
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
A novel thioboration reaction for terminal alkynes offers precise control over cis- and trans-vinyl boron/sulfide synthesis. This metal-free method provides versatile, functionalized derivatives efficiently.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Thioboration reactions are crucial for synthesizing vinyl boron and sulfide compounds.
- Controlling regioselectivity, stereoselectivity, and chemoselectivity in these reactions remains a challenge.
Purpose of the Study:
- To introduce a new, metal-free thioboration reaction for terminal alkynes.
- To achieve on-demand, highly controllable cis- and trans-thioboration.
Main Methods:
- Development of a novel elementoboration reaction.
- Application to terminal alkynes for thioboration.
Main Results:
- Demonstration of highly controllable regio-/stereo-/chemoselective cis- and trans-thioboration.
- Straightforward synthesis of versatile vinyl boron/vinyl sulfide derivatives.
- The reaction proceeds without the need for a transition-metal catalyst.
Conclusions:
- The developed thioboration method offers a powerful and efficient route to functionalized vinyl boron and sulfide compounds.
- This metal-free approach provides significant advantages in synthetic versatility and control.
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