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A simple synthetic methodology to cyclophanes containing hydroxyl groups has been reported. The key steps involved here are: Grignard reaction, double Claisen rearrangement, and ring-closing metathesis. The strategy reported here is protecting group-free synthesis.

Ring-closing metathesis (RCM) is a useful protocol for assembling macrocycles. To synthesize normuscopyridine, and its analogues we used RCM as a key step in our strategy. Our approach to the synthesis of pyridine macrocycles involves two routes. The first approach starts with alkenylation of 2,6-bis[(phenylsulfonyl)methyl]pyridine and involves five steps with 10 % overall yield. The second route begins with Grignard addition to pyridine-2,6-dicarbo nitrile, followed by RCM and one-pot removal of the carbonyl group before hydrogenation of the double bond in 28 % overall yield. This approach has only three steps. Neither route involves the use of protecting groups. Various points of diversification are embedded in our strategy and eight different cyclophanes were assembled by adopting a general approach to these macrocyclics.

A new method to synthesize para-cyclophanes and longithorone C frameworks is reported involving alkylation, ceric ammonium nitrate oxidation and ring-closing metathesis as key steps.

It is found that the configuration of the double bond formed during the RCM depends on the order of the synthetic route.

We demonstrate a new synthetic strategy to cyclophanes containing thiophene and indole moieties via Grignard addition, Fischer indolization and ring-closing metathesis as key steps.

Here, we report a new and diversity-oriented approach to macrocyclic cyclophanes by a Grignard reaction, followed by Fischer indolization and ring-closing metathesis (RCM) as key steps. The configuration of the double bond formed during the RCM depends upon the order of synthetic sequence used. Fischer indolization followed by RCM delivers the cis isomer, whereas RCM followed by Fischer indolization gives the trans isomer.

We demonstrate a new synthetic strategy to cyclophanes containing thiophene and indole moieties via Grignard addition, Fischer indolization and ring-closing metathesis as key steps.

Ring-closing metathesis (RCM) is a useful protocol for assembling macrocycles. To synthesize normuscopyridine, and its analogues we used RCM as a key step in our strategy. Our approach to the synthesis of pyridine macrocycles involves two routes. The first approach starts with alkenylation of 2,6-bis[(phenylsulfonyl)methyl]pyridine and involves five steps with 10 % overall yield. The second route begins with Grignard addition to pyridine-2,6-dicarbo nitrile, followed by RCM and one-pot removal of the carbonyl group before hydrogenation of the double bond in 28 % overall yield. This approach has only three steps. Neither route involves the use of protecting groups. Various points of diversification are embedded in our strategy and eight different cyclophanes were assembled by adopting a general approach to these macrocyclics.

A short synthetic approach to the macrocyclic framework of longithorone C is described via ring-closing metathesis using the Grubbs 2nd generation catalyst.