Redox-Modulated Recognition of Tetrazines Using Thioureas

Abstract

Reduced 1,2,4,5-tetrazines serve as two-point hydrogen-bonding acceptors for thiourea. This host-guest system does not exhibit significant binding in the neutral state, making the complex an electrochemical "on/off" switch.

Enhancing Magnetic Communication between Metal Centres: The Role of s‐Tetrazine Based Radicals as Ligands

“…Molecular recognition coupled with electrochemistry generates synthetic host–guest systems the binding strength of which can be modulated by the ability of the host to accept or donate electrons. Rotello and co‐workers tested tz derivatives as potential candidates for redox modulation via two‐point hydrogen bonding [53] . They demonstrated that tetrazines can be used as molecular “on/off” switches due to their reversible electrochemical behaviour at relatively high negative potentials.…”

“…Rotello and co-workers tested tz derivatives as potential candidates for redoxm odulation via two-point hydrogen bonding. [53] They demonstrated that tetrazines can be used as molecular "on/off" switches due to their reversible electrochemical behaviour at relatively high negative potentials. In this example, the addition of an electron turned" on" the hydrogen bondingb etween the tetrazine ring and thiourea,w hile re-oxidation of the tetrazine moiety leads to decomposition of the complex.…”

Mononuclear and One‐Dimensional Cobalt(II) Complexes with the 3,6‐Bis(picolylamino)‐1,2,4,5‐tetrazine Ligand

“…The 1,2,4,5‐tetrazine (TTZ) ring constitutes an interesting platform for mono‐ and ditopic ligands, as the resulting metal complexes can benefit from (i) the strong electron‐withdrawing character of the platform, which allows access to stable radical anion species, (ii) the occurrence of anion–π interactions in the solid state and (iii) emission properties that are highly dependent on the substitution scheme Accordingly, symmetric ditopic ligands, prepared either by a modified Pinner synthesis involving the condensation of the corresponding nitriles[1b] or by nucleophilic substitution of the chloro substituents in 3,6‐dichloro‐TTZ, provided a series of dimetallic complexes or coordination polymers . Such ligands include 3,6‐dipyridyl‐TTZ and its analogues, 3,6‐dipyrimidyl‐TTZ,[3f], 3,6‐dibenzocarboxylate‐TTZ, 3,6‐dicarboxymethyl ester and, more recently, 3,6‐bis(hydrazine)‐TTZ . Moreover, the nucleophilic monosubstitution of 3,6‐dichloro‐TTZ allowed the preparation of monotopic chelating ligands such as dipicolylamine‐TTZ and pyrazolyl‐TTZ derivatives and complexes.…”

The preparation of 3,6‐bis(3‐hexylthien‐2‐yl)‐s‐tetrazine and its conjugated polymers

“…Owing to the successful work on developing sulfur‐assisted Pinner synthesis of Tz unit in conjugated molecules by Abdel‐Rahman,2, 3 and the recent extensive study on the synthesis of a wide range of tetrazines by Audebert,4 the development of new conjugated Tz structures in conjugated small molecules1–4 and polymers has achieved significant progresses 4(a), 5. These materials showed a great potential for the use in optical and electronic devices such as nonlinear optical devices,6 sensors,7 and smart windows 8. The highly electron‐deficient property of Tz unit is extremely attractive for constructing push–pull structures in pendent groups for nonlinear optical applications1(a), 6 and inside polymer main chains for solar cell applications 9.…”