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Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
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B(C6F5)3- and HB(C6F5)2-mediated transformations of isothiocyanates
Malte Fischer1, Marc Schmidtmann1
1Institute of Chemistry, Carl von Ossietzky University Oldenburg, Carl von Ossietzky Straße 9-11, D-26129 Oldenburg, Germany. malte.fischer@uni-oldenburg.de.
Chemical Communications (Cambridge, England)
|May 5, 2020
Summary
This study explores reactions between isothiocyanates and boranes. New pathways were discovered for synthesizing stable adducts and B,N,C,S heterocycles, offering novel routes to thioformamides.
Area of Science:
- Organoboron chemistry
- Isothiocyanate reactivity
- Heterocyclic compound synthesis
Background:
- Boranes, particularly those with perfluorophenyl substituents, are versatile reagents in synthetic chemistry.
- Isothiocyanates are valuable building blocks for various organic transformations.
- Understanding the reactivity of these functional groups is crucial for developing new synthetic methodologies.
Purpose of the Study:
- To investigate the reactions of isothiocyanates with tris(pentafluorophenyl)borane (B(C6F5)3) and bis(pentafluorophenyl)borane (HB(C6F5)2).
- To explore the formation of novel adducts and heterocyclic structures.
- To establish new synthetic routes to thioformamides.
Main Methods:
- Reaction of alkyl-substituted isothiocyanates with B(C6F5)3.
- Treatment of isothiocyanates with HB(C6F5)2.
- Hydrolysis of hydroboration products.
Main Results:
- Rearrangement reactions of alkyl-substituted isothiocyanates with B(C6F5)3 yield stable thiocyanate-B(C6F5)3 adducts.
- 1,2-hydroboration of isothiocyanates with HB(C6F5)2 forms B,N,C,S heterocycles.
- These heterocycles undergo further reactions under non-inert conditions.
- Hydrolysis provides a new synthetic access to thioformamides.
Conclusions:
- Isothiocyanates exhibit distinct reactivity patterns with different borane species.
- The reactions provide access to novel organoboron adducts and B,N,C,S heterocycles.
- This work expands the synthetic utility of boranes and isothiocyanates in organic chemistry.
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