An efficient difluorohydroxylation of indoles using selectfluor as a fluorinating reagent
Riyuan Lin1, Shengtao Ding, Zhuangzhi Shi
1State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Xue Yuan Road 38, Beijing 100191, China.
Organic Letters
|August 11, 2011
Summary
A new method efficiently difluorinates indoles at the C3 position using Selectfluor, yielding valuable 3,3-difluoroindolin-2-ols. This convenient protocol offers a practical route to unique difluorinated compounds.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Medicinal Chemistry
Background:
- Indole derivatives are prevalent in pharmaceuticals and natural products.
- Introducing fluorine atoms can significantly modulate a molecule's properties.
- Efficient methods for synthesizing fluorinated indoles are highly sought after.
Purpose of the Study:
- To develop an efficient method for the difluorohydroxylation of substituted indoles.
- To synthesize 3,3-difluoroindolin-2-ols with good yields.
- To explore the regioselectivity and scope of the reaction.
Main Methods:
- Utilized Selectfluor as an electrophilic fluorinating reagent.
- Performed difluorination of various substituted indoles.
- Investigated the use of alcohols as nucleophiles.
Main Results:
- Achieved efficient difluorination of indole rings regioselectively at the C3 carbon.
- Obtained 3,3-difluoroindolin-2-ols in good yields.
- Synthesized corresponding products in moderate yields when using alcohols as nucleophiles.
Conclusions:
- Developed a practical and convenient protocol for synthesizing 3,3-difluoroindolin-2-ols.
- Demonstrated high regioselectivity at the C3 position of the indole ring.
- Provided an efficient route to unique difluorinated indolin-2-ol structures.
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