An efficient Stork–Danheiser sequence has been developed for the preparation of a
variety of 3-alkynyl-2-(hydroxymethyl)cyclohex-2-en-1-ones in good to excellent yields
from the corresponding 4,6,7,8-tetrahydro-5H-1,3-benzodioxin-5-ones and terminal alkynes. Several of the 3-alkynyl-2-(hydroxymethyl)cyclohex-2-en-1-one
products were catalytically cyclized to give the corresponding 3-aryl-1,5,6,7-tetrahydro-8H-isochromen-8-ones.
Key words
alkynylations - Stork–Danheiser sequences - vinylogous esters - alkynes - cyclizations
- chromenones