IISER MOHALI

Abstract: Recently, we developed an unprecedented, metal-free, three-step, sustainable catalytic asymmetric desymmetrization of conformationally flexible 2-alkyl-2-(3-oxobutyl)-cycloheptane-1,3-diones to produce library of chiral Swaminathan ketones, which are part of many natural products and drugs. The most crucial and essential ongoing global research is to convert the abundantly available feedstock into materially and medicinally valuable scaffolds in a greener mode. This requires the proper selection of feedstock and the development of systematic green synthetic strategies to convert it into valuable entities. One of the most attractive and abundant feedstocks is lawsones. However, the selective removal of the enolic hydroxy group from the dynamic tautomers of lawsones to access 1,2- and/or 1,4-naphthoquinones, which have plenty of synthetic applications, remains a challenge. Recently, we reported metal-free, chemo-/regio-selective high-yielding hydrodehydroxylation (HDH) strategies in which the abundantly available 3-alkyllawsones were treated with aqueous HI in AcOH under microwave irradiation for a few minutes to access a vast library of materially and medicinally important 1,2-naphthoquinones. We also reported the short total synthesis of medicinally important drug molecules, such as deoxyneocryptotanshinone, miltirone, and vitamin-K3 (menadione) and their analogues, using the currently developed HDH as a key reaction. This lecture will discuss the saga of these reaction’s development.

Tea/coffee: 3:45 PM