The first total synthesis of euplectin, a rare metabolite with a chromone annulated indenone motif, has been accomplished in 17 steps. This has been possible through interplay among three key reactions: a Hauser sulfoxide annulation, a new chromone formation and a late-stage retro-Diels-Alder reaction. The entire regiochemical integrity of the successful route is established by an iodine-catalyzed aromatization of a cyclohexane-1,3-dione and the Hauser annulation.

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The phenols are key intermediates as well as desired products in many target oriented syntheses. The conversion of CÀ H bond to CÀ O bond is one of the most challenging tasks in organic synthesis. In last few decades, the hydroxylation of aromatic compounds has drawn a considerable attention because of their importance in Pharmaceutical industry, material chemistry, polymers and in agrochemicals. Indeed, transition-metal-catalyzed, coordination-assisted regio-and chemoselective orthohydroxylation of arenes has become very efficient and popular strategy to obtain good yields of phenols with tolerance of a wide range of functional groups. This review is the comprehensive summary of recent advancement on Pd-, Ru-, Rh-, Cu-and Ir-catalyzed, chelation-controlled regioselective ortho-CÀ H bond hydroxylation of aromatic compounds in the presence of diverse hydroxylating agents. The review has been classified on the sources of hydroxylating agents used in reaction.

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The synthesis of stilbenoids and styryl carboxylic acids is accomplished with high E-stereoselectivity by olefination of aldehydes with thiophthalides under basic conditions. The olefination is highly atom-efficient as it only loses elemental sulfur during the reaction. This olefination, in conjunction with retro Kolbe-Schmitt reaction, allows facile synthesis of E-hydroxystilbenoids with minimal employment of protecting groups. This study also discloses two important findings: formation of i) 4-methylsulfanyl isocoumarins and ii) an 2-arylindenone.