Synthesis of Fluorenes and Dibenzo[g,p]chrysenes through an Oxidative Cascade

We have developed robust, operationally simple syntheses of fluorenes and of dibenzo[g,p]chrysenes through oxidative cascade processes. These structures that are commonly encountered in optoelectronic materials, dyes, and pharmaceutical products are accessible from 1,4-dioxaspiro[4.5]decan-8-one. The reactions are conducted open to air with inexpensive, safe CuBr₂ or CuCl₂.

Catalytic dehydrogenative aromatization of cyclohexanones and cyclohexenones

Prompted by the scant attention paid by published literature reviews to the comprehensive catalytic dehydrogenative aromatization of cyclohexa(e)nones, this review describes recent methods developed to-date involving transition-metal-catalyzed oxidative aromatization and metal-free strategies for the transformation of cyclohexa(e)nones to substituted phenols.

Tryptophan/copper-catalyzed aromatization reaction of chiral cyclohexanones to phenols

By merging organocatalysis with copper catalysis, a highly efficient stereospecific approach for the synthesis of chiral phenols from cyclohexanones has been developed for the first time. The aromatization reaction proceeds through the in situ formation of enone intermediates and further subsequent bromination/dehydrobromination reactions. And a series of functionalized phenol derivatives are obtained in good yields (up to 89%) and good to excellent enantioselectivities (up to 99% ee).