Reactivity of hydroxy- and aquo(hydroxy)-λ3-iodane-crown ether complexes
Kazunori Miyamoto1, Yukie Yokota, Takashi Suefuji
1Graduate School of Pharmaceutical Sciences, University of Tokushima, 1-78 Shomachi, Tokushima 770-8505 (Japan). kmiya@tokushima-u.ac.jp.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|March 20, 2014
Summary
New shelf-stable hydroxy(aryl)-λ(3)-iodane-[18]crown-6 complexes offer potent oxidation capabilities in water. These reagents efficiently oxidize various organic compounds and serve as precursors for synthesizing diverse iodanes in aqueous media.
Area of Science:
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Hypervalent iodine compounds are versatile oxidants.
- Developing stable and water-compatible hypervalent iodine reagents remains a challenge.
Purpose of the Study:
- To design and synthesize novel hydroxy(aryl)-λ(3)-iodane-[18]crown-6 complexes.
- To investigate their reactivity and utility in aqueous media for oxidation reactions and iodane synthesis.
Main Methods:
- Synthesis of hydroxy(aryl)-λ(3)-iodane-[18]crown-6 complexes from iodosylbenzene derivatives and superacids with [18]crown-6.
- Evaluation of reagent stability, shelf-storage, and oxidizing ability in water.
- Testing reactivity towards phenols, sulfides, olefins, silyl enol ethers, and alkyl(trifluoro)borates.
- Assessing the complexes as progenitors for diaryl-, vinyl-, and alkynyl-λ(3)-iodane synthesis.
Main Results:
- The designed complexes are non-hygroscopic and shelf-storable.
- They exhibit high oxidizing ability in aqueous media under mild conditions.
- Effective oxidation of a range of organic substrates was achieved.
- The complexes successfully served as precursors for synthesizing various iodanes in water.
Conclusions:
- Hydroxy(aryl)-λ(3)-iodane-[18]crown-6 complexes represent stable, water-compatible hypervalent iodine reagents.
- These complexes offer a green and efficient platform for oxidation and iodane synthesis in aqueous environments.
- The methodology is applicable in various organic solvents, enhancing its versatility.
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