Sulfone-based cyanations

This technique has found the following applications in addition to those discussed in Sections 10.1 (resin cure studies on phenol urethane compositions) [65], 12.2 (photopolymer studies [66-68]), and 13.3 (phase transitions in PE) [66], Chapter 15 (viscoelastic and rheological properties), and Section 16.4 (heat deflection temperatures) epoxy resin-amine system [67], cured acrylate-terminated unsaturated copolymers [68], PE and PP foam [69], ethylene-propylene-diene terpolymers [70], natural rubbers [71, 72], polyester-based clear coat resins [73], polyvinyl esters and unsaturated polyester resins [74], polyimide-clay nanocomposites [75], polyether sulfone-styrene-acrylonitrile, PS-polymethyl methacrylate (PMMA) blends and PS-polytetrafluoroethylene PMMA copolymers [76], cyanate ester resin-carbon fibre composites [77], polycyanate epoxy resins [78], and styrenic copolymers [79]. 

The oxidation of 130 by oxygen under pressure was developed af lab scale. Under optimal conditions, the substrate/bisulfite mixture was added to a solution of 130 (3.9 g/1), MAON401 and catalase over 20h. Substrate 130 (65g/l) was converted to sulfonate 133 with a small amount of 131 (<10%). The enzyme reaction stream was telescoped for cyanation to afford only trans-nitrile 134 in 90% yields from 130. Subsequenfly the nitrile was transformed to the methyl ester and the product was converted to the free base 132. In the final step the free base was crysfallized to afford 135 in 56% yield and >99% ee. The conditions of the procedure were successfully applied to pilot plant scale. Compared with the resolution method in the enzymatic process the product yield was increased by 150%, raw material use was reduced by 59.8%, consumption of water was reduced by 60.7%, and the overall process waste was reduced by 63.1% [167]. 

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