An Easy Access to Aryl Azides from Aryl Amines under Neutral Conditions

Abstract

A variety of substituted aryl amines were transformed into aryl azides using t-BuONO and moist NaN₃ in t-BuOH in good to excellent yields. Smooth transformation was observed with anilines, having electron withdrawing and donating groups. Both acid- and base-sensitive groups survived the reaction conditions.

Key words

amines - azides - anilines - diazo compounds - sodium azide

References

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9

GC analysis showed the presence of ca. 40% t-BuOH in t-BuONO. This reagent could be stored in the refrigerator (4 °C) for one week. However, t-BuONO stored more than a week was not as effective and larger excess of reagent was needed for completion of the reaction. The amount of t-BuONO was calculated on the basis of 60% purity.

11

Isoamyl nitrite was purchased from Aldrich Chemical.

12

2-Aminobenzoxazole did not undergo transformation to corresponding azide under the reaction conditions.