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Please login to access the full content or check if you have access via Variation 4: Of Ketene Acetals and Acrylic or Maleic Acid Derivatives

DOI: 10.1055/sos-SD-026-00397

Salaün, J.Science of Synthesis, (200526570.

Ketene diethyl acetal undergoes thermal [2+2] cycloaddition with acrylic ester or acrylonitrile to form cyclobutanone acetals 62, which readily provide cyclobutanones 63 after simple hydrolysis with sulfuric acid (Scheme 25).[‌64‌,‌65‌] This method for the preparation of cyclobutanones is complementary to the procedure involving the cycloaddition of ketenes to alkenes (cf. Section, which is generally limited to electron-rich alkenes.

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