Micelle-Assisted Annulation of β-Naphthols with Ynals: In Water Synthesis of Biaryl Naphtho[ <i>b</i> ]furans

A 1,4-diazabicyclo[2.2.2]octane (DABCO)-mediated synthesis of biarylnaphthofurans has been accomplished in micellar medium by reacting β-naphthols with ynals. Operationally, the transformation occurs in water involving the one-pot condensation/1,4-addition/5-exo-dig cyclization and 1,3-H-shift reactions in a cascade manner. The successful implementation of the reaction on a gram scale, along with the efficient recycling of the micellar medium over five consecutive cycles without a significant loss of activity, underscores the practical utility of the methodology. Transmission electron microscopy (TEM) studies demonstrated that the morphological evolution strongly supports the concept of dynamic micellar catalysis, wherein the structural adaptability of micelles enhances the efficiency of organic transformations in micellar media. In model biaryl naphthofurans, the lone sp³ center was functionalized to extend conjugation within the ring system, thereby fine-tuning their potential photophysical properties.