TCI C1177 5-Chloro-1,3,3-trimethyl-2-methyleneindoline is an exo-methylene indoline derivative and the chlorinated analogue of the compound widely known as Fischer's base. Its structure carries an exocyclic methylene group conjugated with the nitrogen atom of the indoline ring, an arrangement that makes it a carbon nucleophile with distinctive reactivity. In dye chemistry and materials chemistry laboratories, this family of compounds serves as a principal starting material for constructing cyanine and merocyanine dyes, as well as photochromic compounds such as spiropyrans and spirooxazines that are widely studied for optical applications.
The property that makes this material a preferred choice is its ability to undergo condensation with aromatic aldehydes, heterocyclic salt derivatives, and other electrophiles to form long conjugated systems that absorb visible light strongly. The two methyl groups at the gem position keep the framework rigid and block certain side-reaction pathways, while the methylated nitrogen directs electron delocalisation along the desired route. The chlorine substituent on the benzene ring shifts the electronic character of the system, so the absorption and emission wavelengths of the resulting dyes can be tuned relative to the unsubstituted parent compound.
In Indonesian laboratories, this building block is typically used in university research groups and institutional laboratories working on functional dyes, photochromic materials, and organic optical compounds. It is generally handled on a synthetic scale in fume-hooded organic chemistry work, where it is weighed out and condensed with the appropriate partner before purification and spectroscopic characterisation of the resulting conjugated product.
- Cyanine dye synthesis: the reactive exocyclic methylene carbon condenses readily with suitable electrophilic partners to build the extended polymethine chain that gives cyanine dyes their strong visible absorption.
- Merocyanine preparation: condensation with aromatic aldehydes and related carbonyl partners delivers donor-acceptor conjugated systems, with the chlorine substituent available as a handle for tuning the electronic character.
- Spiropyran photochromic materials: the indoline framework with its gem-dimethyl group and methylated nitrogen forms the core half of spiropyran structures studied for reversible light-driven colour switching.
- Spirooxazine synthesis: the same indoline nucleus is carried into spirooxazine photochromes, where the rigid framework suppresses side reactions during ring formation and subsequent handling.
- Heterocyclic building block research: as a chlorinated Fischer's base analogue, it lets researchers compare substituted and unsubstituted systems and map how ring substitution shifts absorption and emission wavelengths.
| Brand | TCI |
|---|---|
| CAS number | 6872-17-9 |
| Molecular formula | — |
| Purity | — |
| Category | Chemistry > Building Blocks > Heterocyclic Building Blocks |
| Pack sizes | available in the catalogue pack sizes offered by TCI for this product code |
| Physical form | — |
| Storage | store according to the conditions stated on the manufacturer's label and safety data sheet |
- Chemical name: 5-Chloro-1,3,3-trimethyl-2-methyleneindoline
Store the container tightly closed in a cool, dry, well-ventilated area away from heat sources, direct sunlight, and incompatible materials, following the conditions stated on the manufacturer's label and safety data sheet. Keep the material in its original supplier container, or in a clean, chemically compatible and clearly labelled vessel if transferred. Handle all weighing and transfer operations in a fume hood, wearing safety glasses, chemical-resistant gloves, and a laboratory coat. Minimise exposure to air and moisture during use, reseal the container promptly after dispensing, and dispose of residues and contaminated materials as chemical waste in accordance with institutional procedures.
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