Original Article:
Aniline Catalysed Hydrazone Formation Reactions Show a Large Variation in Reaction Rates and Catalytic Effects
Fanny Trausel, et al.
Materials Letters, 2019, 238, 267–270.
10.1002/adsc.201800342
Hydrazone-forming reactions between aldehydes and hydrazides are a convenient class of bioorthogonal copper-free click reactions because they proceed in water. In addition, hydrazone formation reactions are widely used in dynamic combinatorial chemistry because they proceed under ambient conditions and are susceptible to catalysis. In this work, the researchers compared a series of hydrazone-forming reactions catalyzed by aniline. It was found that there may be an order of magnitude difference in the reaction rate constants between different hydrazone formation reactions, i.e. aniline catalyzed only part of the hydrazone formation reactions tested. These findings may assist readers in choosing an appropriate hydrazone-forming reaction for their experimental purposes.
An overview of the aniline-catalyzed accelerated hydrazone formation reaction is shown in the figure. Important aniline-catalyzed accelerated hydrazone formation reactions conclusions include:
> Reactions 2, 3, 13 and especially reaction 12, 15, 17 and 9 show a large increase in reaction rate in the presence of aniline.
> Overall, hydrazone formation of NBD-hydrazide and sulfonated benzaldehyde (reaction 3), or acylhydrazide and p-nitrobenzaldehyde or benzaldehyde (reaction 12, 15, 17, 13 and 9) are significantly accelerated by aniline catalysis without observed side reactions, making them useful benchmark reactions to test aniline catalysis or in designing responsive materials where aniline catalysis plays a role.
Chemicals Related in the Paper:
| Catalog Number | Product Name | Structure | CAS Number | Price |
|---|---|---|---|---|
| ACM62523 | AnilineGr |  |
62-52-3 | Price |
| ACM100849374 | Aniline(13c6) |  |
100849-37-4 | Price |
| ACM14545234 | Aniline-d7 |  |
14545-23-4 | Price |
