Synthesis poly azulene

Synthesis of Azulenes. Reaction of tropylium cations with allenylsilanes produces substituted azulenes. Typically, commercially available tropylium tetrafluoroborate (2 equiv) is ert5)loyed. The second equivalent dehydrogenates the dihydroazu-lene intermediate to produce the aromatic product. Poly(4-vinyl-P3Tidine) (poly (4-VP)) or methyltrimethoxysilane is used to scavenge the HBF4 produced in the reaction. 

Write down the structures of the doped and pristine forms of one member of the following classes (discussed in this chapter), and outline one chemical and one electrochemical (if available) synthesis for it P(T) P(T) derivatives P(PP) and related polymers poly(azulenes) ladder polymers poly (quinolines). In which cases are electrochemical (or chemical) polymerizations unavailable, and why ... 

The condensation of a vinylogous formamide with an enamine has been applied to an aza azulene synthesis (351). The point of attachment of the aldehyde to the enamine in condensations with indolenin derived poly-enamines was found to favor the second double bond (352,353). 

The improved electrochemical synthesis (7) of poly pyrrole has led to its use as coating for the protection of n-type semiconductors against photocorrosion in photoelectrochemical cells. (8,9) Recently, it was announced that pyrrole was not the only five-membered heterocyclic aromatic ring compound to undergo simultaneous oxidation and polymerization. Thiophene, furan, indole, and azulene all undergo electrochemical polymerization and oxidation to yield oxidized polymers of varying conductivities (5 x 10 3 to 102 cm- ). (10-13) The purpose... 

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