A Fluorinating Hypervalent Iodine(III) Reagent: 4-Iodotoluene Difluoride

Introduction

There is a great interest of organic chemists in hypervalent iodine reagents because a wide range of reactions can be performed selectively under mild conditions and, in some cases, catalytically. [1] Fluorinated molecules are highly valuable due to the unique characteristics displayed by the fluorine atom. [2]

4-Iodotoluene difluoride (p-TolIF₂, 1) is a hypervalent ­iodine reagent that promotes chemoselective fluorinations avoiding the use of fluorine gas, as well as the expensive xenon difluoride. Several N-fluoro compounds have been developed as stable and effective fluorinating reagents; their preparation, however, generally demands the use of fluorine gas. Compound 1 is usually preferred over its ­iodobenzene difluoride analogue because of easier preparation, purification, and handling.

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