New synthetic strategies to indolocarbazoles have been reported via two-fold Fischer indolization under green conditions using l-(+)-tartaric acid and N,N-dimethyl urea. Starting with cyclohexanone, a bench-top starting material, this methodology has been extended to the total synthesis of natural products such as tjipanazoles D and I as well as the core structure of asteropusazole and racemosin B. Here, atom economical reactions like ring-closing metathesis, enyne-metathesis, and the Diels-Alder reaction have been used as key steps. Diverse strategies demonstrated here are useful in medicinal chemistry and materials science to design a library of decorated indoles.

A concise and simple synthetic approach to cis-syn-cis-triquinanes and -propellanes has been demonstrated via olefin metathesis starting with exo-nadic anhydride. This approach involves a ring-opening and ring-closing metathesis sequence of norbornene derivatives using Grubb's catalyst. Early-stage diallylation of norbornene derivatives is demonstrated followed by ring-closing metathesis that delivers propellanes exclusively. Surprisingly, ring-opening metathesis, late-stage diallylation, followed by ring-closing metathesis delivers triquinane as well as propellane derivatives.

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We have developed an efficient synthetic strategy to assemble C 3-symmetric molecules containing propellane moieties as end groups and a benzene ring as a central core. The synthesis of these C 3-symmetric molecules involves simple starting materials. Our approach to C 3-symmetric compounds relies on a Diels–Alder reaction, cyclotrimerization and ring-closing metathesis as key steps.