Phenolic resins synthesis route

By carbonization of a thin layer of phenolic resin on the suitable templates, Gierszal et al. [108] reported the synthesis of one kind of uniform carbon film with large pore volumes (6 cm g for 24 mn silica colloids), uniform pore sizes, and controlled thickness. This synthetic route involves the formation of a uniform polymeric film on the silica pore walls of silica colloidal crystals or colloidal aggregates and its carbonization and tanplate removal. After proper pre-treatment of the sihca... 

Phenol is one of the most important intermediates of the chemical industry. The global capacity for its production was around 10 Mt/y in 2008, with an actual production around 8.7 Mt. About 40% of the produced phenol is used for the synthesis of bisphenol A, a monomer for polycarbonates. Another 30% is consumed in the production of phenolic resins. The most important route for the industrial production of phenol is, by far, the cumene process, which accounts for 98% of the installed capacity. The cumene process is based upon the researches of Heinrich Hock on the... 

Phenol-formaldehyde resins using prepolymers such as novolaks and resols are widely used in industry. These resins show excellent toughness and thermal-resistant properties, but the general concern over the toxicity of formaldehyde has resulted in limitations on their preparation and use. Therefore, an alternative process for the synthesis of phenolic polymers that avoids the use of formaldehyde is strongly desired. The enzymatic synthesis of phenolic polymers is thus an alternative, interesting and sustainable route. 

Phenolic polymers and phenol-formaldehyde resins are of great commercial interest for a number of electronic and industrial applications (7). However, there have been serious concerns regarding their use due to various toxic effects of formaldehyde and harsh synthesis environments (2). Peroxidase-catalyzed oxidative polymerization of phenol and substituted phenols provides an alternate route for the synthesis of phenolic polymers (3,4), The increased interest in this type of enzyme-based polymerization is mostly due to its environmental compatibility and potential for producing industrial polymers in high yield (5). 

We have focused our attention on the solid phase synthesis of such compounds and described our results here. Alternative routes for the preparation of peptide aldehydes and side-chain protected peptide aldehydes in solid phase synthesis are described. Three new linkers that are stable tmder classical Fmoc or Boc strategies have been developed to obtain the peptide aldehyde from the solid support. One of these linkers was conceptualized on the basis of the Weinreb amide (49) and the other on the basis of phenolic esters (50). Both strategies required the reduction with hydrides of the peptide-linker-resin to release the peptidic aldehydic function. The use of these two different approaches was demonstrated by the synthesis of N-protected a-amino-aldehydes and peptide aldehydes, llie third approach used the ozonolysis reaction for the generation of the desired aldehyde. This concept requires a linker incorporating a double bond in the a-position of the asymmetric carbon of the C-terminal residue that will be cleaved by ozone to produce the carbonyl function. 

The selective oxidation of aromatic rings plays a central role in organic synthesis [1, 2] and biological systems [3], Phenols are important antioxidants and intermediates in the production of resins, plastics, fine chemicals, and pharmaceuticals [1, 4]. Quinones serve as versatile building blocks en route to many biologically active compounds [2, 5-7]. Scheme 14.1 presents examples demonstrating utUity of nuclear aromatic oxidation in the production of vital fine chemicals. 

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