Polymers Containing Cyclobutadiene Complexes

Chapter 2 dealt with so-called symmetric sandwiched metallocenes. In addition to these more traditional symmetric metallocenes, a wide variety of metal-containing macromolecules exist where the metal is bonded to a lone ring system or to an asymmetric sandwich-like system. As in the case of the symmetric metallocenes, attachment of the metal is via it or n-type bonding. Here, the metal is 

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Bunz et al. explored the possibility of doping PPE chains covalently with small amounts of fluorescence-quenching cyclobutadiene complexes, in order to endow their optical properties to the base polymer, PPE [80]. Due to their extensive experience of cyclobutadiene complexes in polymer synthesis [81], the authors prepared several polymers PAE-CoCpl-5 (Table 4) containing different contents of CoCp complexes. The quantum yields were determined by simple comparison of the intensities of the emitted light to that of a standard... 

POLYMERS CONTAINING METALLACYCLOPENTADIENE RINGS AND CYCLOBUTADIENE RINGS COORDINATED TO CYCLOPENTADIENYL METAL COMPLEXES... 

Scherf, U., Stitzer, K., zur Loye, H.-C., and Bunz, U.H.F. (2001) Conjugated organometallic polymers containing Vollhardt s cyclobutadiene complex aggregation and morphologies. Ghem. Ear. 

Ph-C=C-A-C=C-Ph (A = / -phenylene, 4,4 -bipheny-lene, /J-C6H4CH2CH2-P-C6H4) [140]. This reaction gives polymers 68a-c, with = 9600, 5100 and 4200, respectively. These polymers can be used for chemical transformation based on the established chemistry of cobaltacyclopentadiene complexes [154]. Pyrolysis of 68a in THF in a sealed tube at 110°C gives a product with cyclobutadiene complex units, 69 [155] and reaction of isocyanates a product containing 2-pyridone units, 70 [156].-... 

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