Facile Synthesis of Halogenated Spiroketals via a Tandem Iodocyclization

A strategy
for the synthesis of spiroketal compounds through a
tandem iodocyclization of 1-(2-ethynylphenyl)-4-hydroxybut-2-yn-1-one
derivatives is presented. This reaction could proceed under very mild
conditions in a short time and avoid the use of expensive and toxic
metal catalysts. Moreover, the resulting halides can be further exploited
by subsequent palladium-catalyzed coupling reactions, which act as
the important intermediates for building other valuable compounds.