2,2'-Bis#2-indenyl# biphenyl is a ligand

Ligand

In coordination chemistry, a ligand is an ion or molecule that binds to a central metal atom to form a coordination complex. The bonding between metal and ligand generally involves formal donation of one or more of the ligand's electron pairs. The nature of metal-ligand bonding can range from...

 used to make complexes of titanium

Titanium

Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....

, zirconium

Zirconium

Zirconium is a chemical element with the symbol Zr and atomic number 40. The name of zirconium is taken from the mineral zircon. Its atomic mass is 91.224. It is a lustrous, grey-white, strong transition metal that resembles titanium...

 and hafnium

Hafnium

Hafnium is a chemical element with the symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in zirconium minerals. Its existence was predicted by Dmitri Mendeleev in 1869. Hafnium was the penultimate stable...

. Zirconium and hafnium complexes made from this ligand were found to be active catalysts for the polymerization of ethylene

Ethylene

Ethylene is a gaseous organic compound with the formula . It is the simplest alkene . Because it contains a carbon-carbon double bond, ethylene is classified as an unsaturated hydrocarbon. Ethylene is widely used in industry and is also a plant hormone...

 and propylene

Propylene

Propene, also known as propylene or methylethylene, is an unsaturated organic compound having the chemical formula C3H6. It has one double bond, and is the second simplest member of the alkene class of hydrocarbons, and it is also second in natural abundance.-Properties:At room temperature and...

. This work has been patented by DSM Research, and their work was further described in a paper in the Journal of Organic Chemistry

Journal of Organic Chemistry

The Journal of Organic Chemistry is a peer-reviewed scientific journal for original contributions of fundamental research in organic and bioorganic chemistry. It is published by the American Chemical Society. Its 2010 impact factor is 4.002....

. The ligand was originally prepared by the Bosnich group at The University of Chicago. One of the original authors was Bill Odenkirk

Bill Odenkirk

Bill Odenkirk is an American comedy writer.Odenkirk was born in Naperville, Illinois. He is the brother of American comedian Bob Odenkirk, and worked as a writer, producer and actor on sketch comedy TV show Mr. Show with Bob and David, which featured his brother as co-star. Odenkirk went on to...

, who later became known for his work on television shows such as Futurama

Futurama

Futurama is an American animated science fiction sitcom created by Matt Groening and developed by Groening and David X. Cohen for the Fox Broadcasting Company. The series follows the adventures of a late 20th-century New York City pizza delivery boy, Philip J...

, The Simpsons

The Simpsons

The Simpsons is an American animated sitcom created by Matt Groening for the Fox Broadcasting Company. The series is a satirical parody of a middle class American lifestyle epitomized by its family of the same name, which consists of Homer, Marge, Bart, Lisa and Maggie...

and Mr. Show

Mr. Show

Mr. Show with Bob and David is an American sketch comedy series featuring former Saturday Night Live writer/actor Bob Odenkirk and stand up comedian/actor David Cross...

.