Thymolphthalein is a phthalein dye used as an acid–base (pH) indicator. Its transition range is around pH 9.3–10.5. Below this pH, it is colorless; above, it is blue. The molar extinction coefficient for the blue thymolphthalein dianion is 38,000 M−1 cm−1 at 595 nm.[2]
| Thymolphthalein (pH indicator) | ||
| below pH 9.3 | above pH 10.5 | |
| 9.3 | ⇌ | 10.5 |
Thymolphthalein is also known to have use as a laxative[3] and for disappearing ink.[4]
Preparation
Thymolphthalein can be synthesized from thymol and phthalic anhydride.
See also
References
- ^ "Thymolphthalein". pubchem.ncbi.nlm.nih.gov.
- ^ Hahn HH; Cheuk SF; Elfenbein S; Wood WB (April 1970). "Studies on the Pathogenesis of Fever: Xix. Localization of Pyrogen in Granulocytes". The Journal of Experimental Medicine. 131 (4): 701–9. doi:10.1084/jem.131.4.701. PMC 2138774. PMID 5430784.
- ^ Hubacher, MH; Doernberg, S; Horner, A (1953). "Laxatives: chemical structure and potency of phthaleins and hydroxyanthraquinones". Journal of the American Pharmaceutical Association. 42 (1): 23–30. doi:10.1002/jps.3030420108. PMID 13034620.
- ^ Katz, David A. (1982). "Disappearing Ink" (PDF). www.chymist.com. Retrieved August 14, 2017.
You must be logged in to post a comment.