Search results
Results from the WOW.Com Content Network
Cyclopentadiene is a highly reactive diene in the Diels–Alder reaction because minimal distortion of the diene is required to achieve the envelope geometry of the transition state compared to other dienes. [11]
1,2,3,4,5-Pentakis(4-butylphenyl)-1,3-cyclopentadiene is an organochemical compound from the diene group and a cyclopentadiene derivative. The anion of this compound is used as a sterically demanding ligand, often abbreviated as Cp [BIG] , in the organometallic chemistry of sandwich compounds .
1,3-Cyclopentanedione is an organic compound with the formula (CH 2) 3 (CO) 2. It is one of two isomeric cyclopentanediones, the other being 1,2-cyclopentanedione. The enol is predicted to be about 1-3 kcal/mol more stable than the diketo form. [1] The enol structure has been confirmed by X-ray crystallography. [2]
The parent cyclopentadienone is rarely encountered, because it rapidly dimerizes. [1] Many substituted derivatives are known, notably tetraphenylcyclopentadienone. Such compounds are used as ligands in organometallic chemistry. [2] The Knölker complex, derived from a substituted cyclopentadienone, is a catalyst for transfer hydrogenation. [3]
Some dienes: A: 1,2-Propadiene, also known as allene, is the simplest cumulated diene. B: Isoprene, also known as 2-methyl-1,3-butadiene, the precursor to natural rubber. C: 1,3-Butadiene, a precursor to synthetic polymers. D: 1,5-Cyclooctadiene, an unconjugated diene (notice that each double bond is two carbons away from the other).
[2] [1] Illustrative of the unusual complexes made possible with these bulky ligands is molecular iron nitrido complex (t Bu 3 C 5 H 2) 2 Fe 2 N 2. [3] In contrast to (C 5 Me 5) 2 Ir 2 Cl 4, (t Bu 3 C 5 H 2)IrCl 2 is monomeric. [4]
Typical examples of this type of complex are group 14 metal complexes such as CpSiMe 3. An example of both is (Cp 2 Fe(CO) 2). It is probable that η 1-Cp complexes are intermediates in the formation of η 5-Cp complexes. Still rarer, the Cp unit can bond to the metal via three carbons. In these η 3-Cp complexes, the bonding resembles that in ...
The anion was first synthesised by Webster in the 1960s [1] and its conjugate acid much later on. [2] More recently Wright has discovered its extensive coordination chemistry. [ 3 ] [ 4 ] By virtue of a combination of mesomeric and aromatic stabilization of its anion, pentacyanocyclopentadiene is a superacid , with an estimated aqueous p K a of ...