Abstract
The [3 + 2] cycloaddition reaction between sodium azide and various organic nitriles proceeds smoothly in the presence of amine salts as catalyst in dimethylformamide. The corresponding 5-substituted 1-H tetrazoles were obtained under mild condition in good to excellent yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.
ACKNOWLEDGMENTS
We thank the State Key Laboratory of Materials-Oriented Chemical Engineering Foundation support of this work. We also thank Xiaoming Ren for his important contribution in the sample analysis of this work.
Notes
a Reaction conditions: benzonitrile (10 mmol), NaN3 (12 mmol, 0.78 g), catalyst (10 mmol), solvent (20 ml), 110 °C, reaction time (8 h).
b Yield of isolated products. Structures confirmed by comparison of IR and 1H NMR with those of authentic materials.
c Catalyst structure A, B, and C (Scheme ).
d Hexadecyl trimethyl ammonium bromide (CTAB).
e Reaction carried out with NaN3 (7 mmol): Py·HCl (10 mmol), yield 58%; NaN3 (12 mmol): Py·HCl (10 mmol), yield 84%; NaN3 (15 mmol): Py·HCl (10 mmol), yield 93%.
a Reaction conditions: aromatic nitrile (10 mmol), NaN3 (12 mmol, 0.78 g), pyridine hydrochloride (0.01 mol, 1.15 g), and DMF (20 ml).
b Yield of isolated products.
a Reaction conditions: nitrile (10 mmol), pyridine hydrochloride (0.01 mol, 1.15 g), and NaN3 (12 mmol, 0.78 g) in DMF (20 ml) for 1c–3c, NaN3 (30 mmol, 1.95 g) in DMF (30 ml) for 5c–8c.
b Isolated yield.
c Glacial acetic acid (30 ml) as solvent.
d Water (30 ml) as solvent.