Design, Development, and Applications of New a-Diazo Carbonyl Compounds as Carbene Surrogates to Access Useful Organic Compounds

Abstract

Carbene is the key reactive intermediate that has been utilized widely in varieties of synthetic transformations ranging from cycloaddition to site-selective functionalizations. Controlling the reactivity of carbenes is the most crucial and foremost parameter for achieving the selective carbene transfer reactions. The combined effect of metal catalysts, reagents and ligands plays a major role for exploring the reactions via singlet carbene intermediate. Contrarily, triplet carbene has gained very little attention from the researchers as its reactivity relied on the use of specific metal complexes, and as such dealing with the reactivity of triplet carbene in organic synthesis is underdeveloped.

To implement the tuneable and unmet reactivity of carbenes for the different cycloaddition reactions via carbene for the construction of small organic molecules, we designed and developed different novel donor-/acceptor-type diazo compounds as carbene precursors or surrogates. We have disclosed the unique reactivity pattern of diazosuccinimide at both of its carbene spin states under different reaction conditions. We have also demonstrated that the synergistic combination of catalyst (early transition-metal based) and reagent (diazoacetate) play a crucial role over benzenoid substrates for the controlled regio- and chemo-selective dearomatization of benzenoids by mobilizing one double bond at the expense of intrinsic aromatic stabilization. We have explored the reactivity of these carbene surrogates under traditional metal catalysis as well as photocatalysis. We have successfully utilized these novel carbenes precursor for the synthesis of various useful compounds and bioactive compounds.