3,4,5,6-Tetrafluorophenylnitren-2-yl: a ground-state quartet triradical

Area of Science:

• Photochemistry
• Organic Chemistry
• Spectroscopy

Background:

• Organic azides are versatile precursors in synthetic chemistry.
• Understanding the photochemical pathways of azides is crucial for developing new synthetic methodologies.
• Fluorinated organic compounds exhibit unique electronic and chemical properties.

Purpose of the Study:

• To investigate the photochemistry of 2-iodo-3,4,5,6-tetrafluorophenyl azide.
• To characterize the photoproducts using spectroscopic techniques.
• To understand the properties of novel organic high-spin molecules.

Main Methods:

• Matrix isolation spectroscopy (IR and EPR) at cryogenic temperatures (4 K).
• UV and visible light irradiation.
• Electronic structure calculations.

Main Results:

• The primary photochemical step involves nitrogen molecule loss, forming phenyl nitrene.
• Further irradiation leads to azirine, ketenimine, nitreno radical, and azirinyl radical.
• A nitreno radical with a quartet ground state was identified and characterized by EPR spectroscopy.
• Product distribution is sensitive to matrix environment and irradiation conditions.

Conclusions:

• The study elucidates the complex photochemical behavior of a fluorinated phenyl azide.
• A new class of organic high-spin molecules, nitreno radicals, has been identified and studied.
• Electronic structure calculations aid in understanding the properties of these novel species.