New synthetic routes to substituted 3-hydroxypyridines 6 are presented. Ring-closing olefin metathesis (RCM)/elimination and RCM/oxidation/deprotection of nitrogen-containing dienes 4 are the key processes of the routes. An application of RCM/oxidation/deprotection to the synthesis of 3-aminopyridine 13f is also described.

The selective synthesis of substituted indoles was achieved by the ring-closing olefin metathesis (RCM)/elimination sequence or the RCM/tautomerization sequence of functionalized pyrrole precursors. The RCM/elimination sequence was also applied to double ring closure to yield a substituted carbazole.

The selective synthesis of substituted 4-vinylindoles by the ring-closing enyne metathesis (RCEM)/dehydration sequence is reported. In contrast with many known methods in which a pyrrole ring is constructed onto a functionalized benzene precursor, this method enables the construction of a benzene ring onto a pyrrole precursor. The RCEM/tautomerization sequence for the synthesis of 7-hydroxy-4-vinylindole is also presented as an application of this method.

Chiral supramolecular boron Lewis acid catalysts were developed with the use of chiral 3-phosphoryl-BINOLs, 2-cyanophenylboronic acids, and tris(pentafluorophenyl)borane based on CN•••B and PO•••B coordination bonds. In particular, coordinated tris(pentafluorophenyl)boranes can increase the Lewis acidity of the active center based on the Lewis acidassisted Lewis acid catalyst system. A possible cavity in these catalysts was highly suitable for some probe Diels-Alder reactions of acroleins with cyclic and acyclic dienes, and the corresponding adducts were obtained in good to high yields with high enantioselectivities.

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