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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. [ABSTRACT FROM AUTHOR]

Various crownophanes are assembled starting with simple phenol derivatives such as catechol, resorcinol, and hydroquinone. Here, cross-enyne metathesis (CEM) and Diels-Alder (DA) reaction have been used as key steps. This strategy has embedded six diversity points. [ABSTRACT FROM AUTHOR]

Two RCM-based approaches to normuscopyridine (Va) and its analogues are explored. [ABSTRACT FROM AUTHOR]

In this review we cover various approaches to meta- and paracyclophanes involving popular reactions. Generally, we have included a strategy where the reaction was used for assembling the cyclophane skeleton for further functionalization. In several instances, after the cyclophane is made several popular reactions are used and these are not covered here. We included various natural products related to cyclophanes. To keep the length of the review at a manageable level the literature related to orthocyclophanes was not included.