Thallium continued

Thallium continues to attract the least attention of the four elements, with less than 10% of papers collected devoted to its chemistry. 

Thallium continues to be by far the least studied of the Group 13 elements, though the level of activity during 1994 has been consistent with the previous year. 

B. ds-1,2-Cyclohexanediol. A 500-ml., round-bottomed flask equipped with a reflux condenser and a magnetic stirring bar is charged with 17.56 g. (0.0667 mole) of thallium(I) acetate (Note 1), 160 ml. of glacial acetic acid, 3.0 g. (3.7 ml., 0.0365 mole) of cyclohexene (Note 3), and 8.46 g. (0.0333 mole) of iodine (Note 4) in the order given. The suspension is stirred and warmed in a heating bath at 80° for 30 minutes. An 80-ml. portion of water is added, stirring is continued, and the mixture is heated at reflux for... 

Platinum complexes (continued) with aryls, thallium adducts, 3, 399 with bis(alkynyl), NLO properties, 12, 125 with bisalkynyl copper complexes, 2, 182-186 with bis(3,5-dichloro-2,4,6-trifluorophenyl), 8, 483 and C-F bond activation, 1, 743 in C-H bond alkenylations, 10, 225 in C-H bond electrophilic activation studies, 1, 707 with chromium, 5, 312 with copper, 2, 168 cyclometallated, for OLEDs, 12, 145 in diyne carbometallations, 10, 351-352 in ene-yne metathesis, 11, 273 in enyne skeletal reorganization, 11, 289 heteronuclear Pt isocyanides, 8, 431 inside metallodendrimers, 12, 400 kinetic studies, 1, 531 on metallodendrimer surfaces, 12, 391 mononuclear Pt(II) isocyanides, 8, 428 mononuclear Pt(0) isocyanides, 8, 424 overview, 8, 405-444 d -cP oxidative addition, PHIP, 1, 436 polynuclear Pt isocyanides, 8, 431 polynuclear Pt(0) isocyanides, 8, 425 Pt(I) isocyanides, 8, 425 Pt(IV) isocyanides, 8, 430... 

An interesting application of thallium is in superconducting materials. Superconductors have no resistance to the flow of electricity. Once an electrical current begins flowing in the material, it continues to flow forever. Thallium is also used in wireless communications. 

Tl,Bi)-1223 or (Tl,Pb)-1223 are selected for detailed description as representatives of the thallium bilayer and monolayer compound, respectively. Tl-2201 is selected because of its structural simplicity and continuously variable T, up to 84 K. It is the ideal candidate for fundamental studies. (Tl,Bi)-1223 and (Tl,Pb)-1223 offer a high irreversibility of field, which is very important for applications in high magnetic field. 

Studies have been continued by Glaser and his co-workers on platinum-thallium clusters. Very large 7ptxi couplings ranging from 48 to 66 kHz have been observed by them for [(NC)5PtTl(en) i] ( = 1-3) complexes where en denotes ethylenediamine. 

The redox properties of thallium are important in preparative organic and organometallic/inorganic chemistry. For this reason, studies of redox behavior and the thermodynamics and kinetics of complexing processes are likely to remain relevant. The employment of the TF ion as a probe for in biological systems will no doubt continue, because of the easy detection of the former. For the same reason, thallium(III) can be used as a representative for several other metal ions in solution. 

Interest in the chemistry of thallium may be enhanced by the development of molecular devices with specific functionalities, such as superconductors, photosensitive devices, solar energy light-harvesting compounds, and ingredients in glass-fiber communication systems. Because of the potential applications, and for fundamental chemical reasons, the chemistry of thallium will continue to attract the attention of (and puzzle) chemists. 

---