Cyclopentadienylthallium

Cyclopentadienylthallium

Names
IUPAC name Thallium(I) cyclopentadienide
Other names Thallium cyclopentadienide (η5-Cyclopentadienyl)thallium
Identifiers
CAS Registry Number	34822-90-7
ChemSpider	24721800 Y
InChI InChI=1S/C5H5.Tl/c1-2-4-5-3-1;/h1-5H;/q-1;+1 Key: CVEQRUADOXXBRI-UHFFFAOYSA-N InChI=1/C5H5.Tl/c1-2-4-5-3-1;/h1-5H;/q-1;+1 Key: CVEQRUADOXXBRI-UHFFFAOYAE
Jmol-3D images	Image
SMILES [cH-]1cccc1.[Tl+]
Properties
Molecular formula	C5H5Tl
Molar mass	269.48 g·mol−1
Appearance	Light yellow solid
Melting point	300 °C (572 °F; 573 K)
Solubility in water	Insoluble
Hazards
EU classification	T+
R-phrases	R26/28, R33, R36/37/38
S-phrases	S13, S28, S45
NFPA 704	0 3 0
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Cyclopentadienylthallium, also known as thallium cyclopentadienide, is an organothallium compound with formula C₅H₅Tl. This light yellow solid is insoluble in most organic solvents, but sublimes readily, and is useful as a precursor to transition metal and main group cyclopentadienyl complexes, as well as organic cyclopentadiene derivatives.^[1]

Preparation

Cyclopentadienylthallium is prepared by the reaction of thallium(I) sulfate, sodium hydroxide, and cyclopentadiene:^[2]

Tl₂SO₄ + 2 NaOH → 2 TlOH + Na₂SO₄

TlOH + C₅H₆ → TlC₅H₅ + H₂O

Applications

Compared to most of other cyclopentadienyl (Cp) transfer reagent such as cyclopentadienyl sodium, CpMgBr and Cp₂Mg, cyclopentadienylthallium is less air sensitive. It is also much less of a reducing agent.

References