Synthesis and characterization of ortho bromo-methoxy aminoazobenzene derivatives

  1. David Martínez-López,
  2. Amir Babalhavaeji,
  3. Diego SampedroORCID Logo and
  4. Andrew WoolleyORCID Logo

Submitting author affiliation: University of Toronto, Toronto, Canada

Beilstein Arch. 2019, 201988.

Published 20 Aug 2019

  • Preprint


Aminoazobenzene derivatives with four ortho substituents with respect to the NN double bond are a relatively unexplored class of azo compounds that show promise for use as photoswitches in biology. Tetra-ortho methoxy aminoazobenzenes, in particular, can form azonium ions under physiological conditions and exhibit red-light photoswitching. Here, we report the synthesis and characterization of two ortho bromo-methoxy aminoazobenzene derivatives. These compounds form red light absorbing azonium ions but only under very acidic conditions (pH <1). While the low pKa makes the azonium form unsuitable, the neutral versions of these compounds undergo trans-to-cis photoisomerization with blue-green light and exhibit slow (τ½ ~10 min) thermal reversion and so may find applications under physiological conditions.

Keywords: azobenzene; azonium; photoisomerization; photoswitch; visible light

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When a peer-reviewed version of this preprint is available, this information will be updated in the information box above. If no peer-reviewed version is available, please cite this preprint using the following information:

Martínez-López, D.; Babalhavaeji, A.; Sampedro, D.; Woolley, A. Beilstein Arch. 2019, 201988. doi:10.3762/bxiv.2019.88.v1

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