Aldolisation of novel PEG-bound α-phenylselenopropionate with aldehydes, followed by oxidation-elimination with 30% hydrogen peroxide and then treatment with potassium thiocyanate formed PEG-bound 2-(thiocyanatomethyl)alk-2-enoates. Subsequent cleavage from the PEG efficiently afforded ethyl (Z)-2-(thiocyanatomethyl)alk-2-enoates in good yields and high purities.
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