Synthesis of 18F-labeled phenolphthalein and naphtholphthalein.
The fluorination of phenolphthalein and naphtholphthalein was performed with diluted fluorine gas under acidic conditions. For both compounds we observed an electrophilic fluorination into ortho position to the hydroxyl group. Through the use of this reaction we synthesized and characterized mono-and difluorinated derivatives of phenolphthalein and naphtholphthalein. The compounds were also prepared in the 18F labeled form, which are usable as a new type of probe for in vivo pH measurement in biological objects using Cerenkov imaging or combination of light absorption and PET.
Kinetics and Equilibria of the Carbinol Formation of Phenolphthalein
Introduction That phenolphthalein fades in concentrated alkali was first observed by A. yon Baeyer.’ The rate of fading and the position of equilibrium were investigated colorimetrically by Kober and Marshall.2 They attributed the fading process to the reaction of equimolecular proportions of alkali and the red form to yield a tribasic salt of phenolphthalic acid and formulated the process as ki
On the ontology of particle mass and energy in special relativity
Einstein claimed that the fundamental dynamical insight of special relativity was the equivalence of mass and energy. I disagree. Not only are mass and energy not equivalent (whatever exactly that means) but talk of such equivalence obscures the real dynamical insight of special relativity, which concerns the nature of 4-forces and interactions more generally. In this paper I present and defend a new ontology of special relativistic particle dynamics that makes this insight perspicuous and I explain how alleged cases of mass–energy conversion can be accommodated within that ontology.