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With the aim of creating new, improved solid supports for organic synthesis, a series of poly(styreneoxyethylene) graft copolymers 6a-d was synthesized by anionic polymerization of ethylene oxide from a polystyrene-supported 1,3-diol 5b. Graft lengths were varied from 29 to 58 repeat units (67-82 wt % polyoxyethylene). The so-formed alcohols 6a-d were further transformed into chlorides 7a-d, amines 8a-d, and two commonly used linkers, Wang 9a-d and HMPB 10a-d. These functional group interconversions were efficiently monitored using gel-phase 13 C NMR, and the solid-state properties of all copolymers were characterized by differential scanning calorimetry. Thermal properties of these materials were found to be dominated by the polyoxyethylene composition. A correlation between the melting point associated with the graft lengths and the physical properties of the resins was observed. The optimum graft copolymer composition, determined by balancing the degree of functional group loading with resin crystallinity and swelling, was found to be in the 0.4-0.5 mmol g -1 range.

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(R)-2-Methylpentanol is an important chiral intermediate for the synthesis of certain medicinally important compounds, natural products, and liquid crystals. Here we describe the development of a practical kinetic resolution utilizing an enantiospecific biocatalytic reduction of racemic 2-methylvaleraldehyde. The process utilizes an evolved ketoreductase enzyme to selectively reduce the (R)-enantiomer of racemic 2-methylvaleraldehyde to the desired product with high volumetric productivity. A scaleable method for separating the desired product from the off-enantiomer of the starting material is also described. The process is cost-effective, green, and amenable to manufacturing scale.

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