19F magnetic resonance probes for detecting formaldehyde

[Display omitted] Herein we report two separate 19F magnetic resonance (MR) probes responsive towards formaldehyde. Both agents were synthesized in a single step via aminoallylation of either 4-fluorobenzaldehyde (1FA) or 4-(trifluoromethyl)benzaldehyde (3FA) with ammonia and allylboronic acid pinac...

Full description

Saved in:
Bibliographic Details
Published in:Tetrahedron letters 2022-05, Vol.98, p.153796, Article 153796
Main Authors: Massing, Justin O., Almounajed, Leila, Minder, Kyle A., Lange, Joseph D., Eltahir, Lina A., Kelts, Jessica L.
Format: Article
Language:English
Citations: Items that this one cites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:[Display omitted] Herein we report two separate 19F magnetic resonance (MR) probes responsive towards formaldehyde. Both agents were synthesized in a single step via aminoallylation of either 4-fluorobenzaldehyde (1FA) or 4-(trifluoromethyl)benzaldehyde (3FA) with ammonia and allylboronic acid pinacol ester. Condensation of the resulting homoallylic amines 1FA and 3FA with formaldehyde, followed by a 2-aza-Cope rearrangement and subsequent hydrolysis affords 4-fluorobenzaldehyde and 4-(trifluoromethyl)benzaldehyde, respectively. In the case of 1FA, this transformation is evidenced by a concomitant downfield shift in the 19F MR signal from −115 ppm to −103 ppm. Further, this transformation is selective towards formaldehyde over other reactive carbonyl species. While 3FA exhibits similar selectivity towards formaldehyde, this more sensitive probe is limited by the small chemical shift difference (0.7 ppm) following its activation.
ISSN:0040-4039
1873-3581
DOI:10.1016/j.tetlet.2022.153796