CN-121974862-A - Method for optically releasing TAD in indole-TAD adduct

Abstract

The application discloses a method for optically releasing a TAD in an indole-TAD adduct, belonging to the technical field of reversible chemical reaction of optical response. The application provides a technical scheme of a method for optically controlling and releasing a TAD in an indole-TAD adduct, which utilizes a C-N bond in the optically activated indole-TAD adduct to realize the release of the TAD by the TAD-indole adduct at a low temperature and realizes the controllable release of the TAD under different illumination (wavelength) conditions by regulating and controlling groups in the indole-TAD adduct. The method has simple operation and mild condition.

Inventors

• LIU XIJIA
• WANG JINGWEN
• Du Leixing

Assignees

• 浙江师范大学

Dates

Publication Date

20260505

Application Date

20260401

Claims (10)

1. 1. A method for optically releasing TAD from an indole-TAD adduct comprising: in an inactive atmosphere, carrying out C-N cleavage reaction on a solution containing the indole-TAD adduct under the illumination condition to release indole and TAD; the indole-TAD adduct is a compound with a structure shown in a formula 1; Wherein R 1 is selected from one of methyl, methoxy, fluorine, chlorine, trifluoromethyl, ethoxycarbonyl and cyano, R 2 is selected from one of phenyl, p-fluorophenyl, naphthyl and pyrenyl, R 3 is selected from one of methyl, ethyl and phenyl, and R 4 is selected from one of phenyl, cyclopentyl and n-butyl.
2. 2. The method of claim 1, wherein the indole-TAD adduct is selected from at least one of the compounds of the structures represented by formulae 1aa, 1ab, 1ba to 1 bd; 。
3. 3. The method of claim 1, wherein the illumination condition comprises an illumination wavelength of 365-460 nm.
4. 4. The method of claim 1, wherein the temperature of the reaction is-20 to 25 ℃.
5. 5. The method of claim 1, wherein the solution comprising an indole-TAD adduct further comprises an additive; The additive is mercaptan or 1, 3-butadiene.
6. 6. The method according to claim 5, wherein the thiol is at least one selected from the group consisting of 2-methylbenzothiool, 3-methylbenzothiool, cyclohexyl thiol, 2-methyl-2-propanethiol, 1-dodecyl mercaptan, and 1-pentanethiol.
7. 7. The method of claim 5, wherein the molar ratio of the indole-TAD adduct to the additive is 1:1-3.
8. 8. The method according to claim 1, wherein the reaction time is 3-13 hours.
9. 9. The method according to claim 1, wherein the solvent in the solution containing the indole-TAD adduct is selected from at least one of acetonitrile, dichloromethane, toluene, acetone.
10. 10. The method according to claim 5, wherein the indole-TAD adduct-containing solution is subjected to C-N cleavage under light conditions to release indole and TAD, and then subjected to thiol conditions to obtain indole and urea; in the mixed solution containing ferric nitrate, sodium chloride, TEMPO and acetone, the indole and the urea have the characteristic of reversely reacting to obtain the indole-TAD adduct.

Description

Method for optically releasing TAD in indole-TAD adduct Technical Field The application relates to a method for optically releasing a TAD in an indole-TAD adduct, belonging to the technical field of reversible chemical reaction of optical response. Background The indole-TAD (1, 2, 4-triazolin-3, 5-dione) adducts can achieve reversible transclick reactions under high temperature or force triggering conditions, releasing highly active TAD molecules. This reversibility gives the TAD-indole system unique advantages in dynamic material design, such as achieving self-repair, shape memory, and recyclability of the material. Indole-TAD adducts contain a dynamically reversible C-N bond which can be activated by increasing temperature or using mechanical force to release highly active TAD molecules, making their use in the fields of biomolecular labeling, smart materials and controlled polymerization increasing in recent years. For example, the prior art discloses a thermally reversible crosslinker based on TAD chemistry that is used to build polyurethane networks by reacting with 2-phenylindole diols to form tetrafunctional crosslinking sites. It has been found that the presence of TAD-indole adduct cross-linking agents allows the material to exchange chemical bonds rapidly at high temperatures, thereby restoring mechanical properties while maintaining structural integrity. The stability of the material in multiple damage/repair cycles was demonstrated by multiple recovery experiments. The prior art discloses highly reactive and degradable Polyaminoamides (PAA) containing indole functional groups, by introducing indole functional groups, utilizing thermally-promoted dynamic C-N bond chemistry of TADs with indole, achieving efficient post-modification and crosslinking of the polyaminoamides and exploring their application in layer-by-layer coating and surface functionalization. The prior art also discloses the use of TAD-indole adducts to thermally release TAD, enabling precise tyrosine-specific protein/peptide modification. Therefore, the dynamic C-N bond chemistry of the TAD-indole adduct has important application value in the fields of materials, biomarkers and the like. It is noted that although thermally and mechanically induced dynamically reversible C-N bonds are viable in some cases, they have found wide application. However, these methods generally require specific conditions in which the thermal control reaction requires at least a temperature higher than 40 ℃, and in which the mechanical triggering reaction requires a TAD-indole adduct having a large side chain, which limits the range of applications of the indole-TAD adduct. Therefore, a novel method is explored to activate the TAD-indole dynamic reversible C-N bond, and the TAD is released by the TAD-indole dynamic reversible C-N bond especially at room temperature or lower, so that the application of the TAD-indole adduct in the fields of biomarkers, intelligent materials and the like is further expanded, and the TAD-indole adduct has important value and significance. Disclosure of Invention In order to solve the problem that conditions of thermal initiation and mechanical initiation in the prior art of dynamic reversible release of an indole-TAD adduct limit the application range of the indole-TAD adduct, the application provides a technical scheme of a method for optically controlling the release of the TAD in the indole-TAD adduct, the TAD is released at a low temperature by utilizing a C-N bond in the optically activated indole-TAD adduct, and the TAD is controllably released under different illumination (wavelength) conditions by regulating and controlling groups in the indole-TAD adduct. The application adopts the following technical scheme: according to a first aspect of the present application there is provided a method of optically releasing a TAD in an indole-TAD adduct comprising: in an inactive atmosphere, carrying out C-N cleavage reaction on a solution containing the indole-TAD adduct under the illumination condition to release indole and TAD; the indole-TAD adduct is a compound with a structure shown in a formula 1; Wherein R 1 is selected from one of methyl, methoxy, fluorine, chlorine, trifluoromethyl, ethoxycarbonyl and cyano, R 2 is selected from one of phenyl, p-fluorophenyl, naphthyl and pyrenyl, R 3 is selected from one of methyl, ethyl and phenyl, and R 4 is selected from one of phenyl, cyclopentyl and n-butyl. Alternatively, the indole-TAD adduct is selected from at least one of the compounds of the structures represented by formulae 1aa, 1ab, 1ba to 1 bd; optionally, the illumination condition comprises that the illumination wavelength is 365-460 nm. Based on the technical scheme, for R 2, the preferable illumination wavelength is 365-375 nm, for R 2, the preferable illumination wavelength is 410-420 nm, for R 2, the preferable illumination wavelength is 455-460 nm. Optionally, the reaction temperature is-20-25 ℃. Optionally, th