0 Hits

  • Previous / Next

You are using Science Of Synthesis as a Guest.
Please login to access the full content or check if you have access via Method 2: Reaction of Phenols with Alkynoates and Alkynoic Acids

DOI: 10.1055/sos-SD-014-00294

Williams, A. C.; Camp, N.Science of Synthesis, (200314384.

The coupling of a phenol with an alkynoate or alkynoic acid represents a method for the preparation of 2H-1-benzopyran-2-ones unsubstituted in the 3-position. The principal reaction conditions involve catalysis by palladium (Scheme 35), acid (Scheme 36), triphenylphosphine (Scheme 37), or zinc (Scheme 38). The milder conditions compared to the Pechmann reaction (Section mean that the functional group compatibility is wider. Developments include the use of sulfonic acid resin catalysts and clays in combination with microwave heating.[‌175‌,‌237‌] Yields are generally good to excellent.[‌70‌,‌175‌,‌237‌‌247‌]