Arylsulfonate resins

Figure 15.8 Arylsulfonate resins and their cleavage by imidazole, thiolates and primary and secondary amines. The sulfonate resin acts as the leaving group in the nucleophilic displacement reaction.

Radel . [Amoco Amoco Eun ] Poly-arylsulfone resins for medical devices, chem. processing, elecVelectronic, food pkg., aviation applies. 

Figure 19 shows the ultraviolet absorption spectrum of a typical diazonaphthoquinone and a common novolac resin. The naphthoquinone sensitizer has a strong absorbance at the 365 nm., 405 nm., and to a lesser extent the 436 nm. mercury emission lines. There are two diazonaphthoquinone isomers that are used in commercial photoresist formulations that are available at this time. The 5-arylsulfonates are by far the most commonly used. A spectrum of a representative of this class of materials is depicted in Figure 20. The 5-arylsulfonate materials are characterized by an absorbance maximum at approximately 400 nm. and a second, slightly stronger maximum at approximately 340 nm.

AZ2400 is different from most other commercial positive photoresists in both formulation and response to mid-UV radiation. This resist is formulated with a resin that is relatively transparent in the mid-UV and l-oxo-2-diazonaphthoquinone-4-arylsulfonate (structure 3.3) rather than the 5-arylsulfonate (structure 3.2) that is commonly used in most commercial photoresists (24). 

These zirconium phosphate materials are being developed as replacements for ion exchange resin catalysts. The arylsulfonic acid MELS have been evaluated for butene isomerization, methanol dehydration, MTBE synthesis as well as cracking, and for the alkylation of aromatics. In the synthesis of MTBE this catalyst appears to out-perform the ion exchange resins, Amberlyst 15. 

In contrast to Si and Ge linkages (traceless linkers) of the aryl ring to the resin where electron-rich aromatic ring systems favor rapid cleavage, the reductive cleavage of arylsulfonates works well with electron-poor aromatic rings. 

Simple diols have been subjected to the pinacol rearrangement in the presence of Amberlyst 15, a polystyrene sulfonic resin with a high concentration of acidic centers. When excess catalyst is used (g catalyst/g diol = 1.25) pinacol gives 3,3-dimethyl-2-butanone in near quantitative yield (batch reactor, 373 K, 2 h) [33]. Of the two isomeric ketones 3,3-diphenyl-2-butanone (10), formed with phenyl migration, is the sole product when 2,3-diphenyl-2,3-butanediol (9) is reacted (Scheme 6). This feature is very similar to that observed under homogeneous conditions in the presence of sulfuric acid [2]. An arylsulfonic silica catalyst prepared by grafting and sulfonation proved to be less selective [33]. 

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