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Highly chemo‐ and enantioselective inter‐ and intra‐molecular oxidative dearomatizing spirocyclization of 1‐alkyl‐2‐naphthols with O2 as the hydrogen acceptor was achieved using an iron catalyst. In the iron complex 1‐catalyzed reaction, 1‐methyl‐2‐naphthols 2 in the presence of phenol derivatives as the nucleophile was selectively oxidized, producing the spirocyclic ketones with good to high enantioselectivities via a tandem strategy. Pre‐synthesized 1,1′‐methylbis(arenol)s 6 and 7, intermediates of the tandem strategy were also converted to the desired products with chemo‐ and enantioselectivity. [ABSTRACT FROM AUTHOR]

Highly enantioselective aerobic oxidative cross-coupling of 2-naphthols with broad substrate scope is achieved by using iron(salan) complex as the catalyst. The scope of the cross-coupling reaction is shown to be different from that of the homocoupling reaction under the same reaction conditions.

The mechanisms involved in the photopromoted Ru-catalyzed asymmetric aerobic oxidation and epoxidation of sulfide are discussed. The application of water as a proton transfer mediator in these reactions is also explained.

Several optical active Nb(salan) complexes are prepared and their oxidation catalysis is examined. Monomeric Nb(salan) complexes prepared in situ from Nb[(OiPr).sub.5] and salan ligands followed by water treatment have catalyzed the epoxidation of allylic alcohols better using aqueous peroxide in CH[Cl.sub.3]/brine or toluene/brine solution with high enantioselectivity , except for the reaction of cinnamyl alcohol.

Iridium(III)-salen complexes have efficiently catalyzed enantioselective carbene Si-H bond insertion. The formation of a chiral silicon center is achieved by the Si-H insertion into prochiral silanes, where the reactions between prochiral silanes and tert-butyl [alpha]-diazopropionate in the presence of {(aR,S), Ar = Ph} has proceeded with high stereoselectivity.

The ability of iridium(III)-salen complexes to efficiently catalyze the enantioselective C-H carbene insertion is demonstrated. An appropriate combination of complexes in the reaction and [alpha]-diazoacetate ([alpha]-aryl-[alpha]-diazoacetates or [alpha]-diazopropionate) as the carbene source is found to achieve the insertion reaction at the [alpha]-position of tetrahydrofuran or at the methylene of 1,4-cyclohexadiene proceeded with high enantio- and diastereoselectivity (up to 99%).

Fe(salan) complexes are efficient catalysts for the asymmetric aerobic oxidative coupling of 2-naphthol derivatives. This reaction is carried out in air with high enantioselectivity and this is the first report for asymmetric oxidation by using molecular oxygen in air and in absence of additives.

The synthesis of a new class of stable and optically active [Ir.sup.III]-salen complexes and the full scope of asymmetric cyclopropanation using the tolyl or phenyl ligand complexes as catalysts is described. The short step synthesis of 8-[(1R,2S)-2-hexylcyclopropyl]octanoate isolated from Escherichia coli B-ATCC 11303 was used as key step to demonstrate the application of cyclopropanation reaction.

Optically active chiral aluminum(salalen) complex is synthesized and it can be used as a catalyst for asymmetric hydrophosphonylation of aldehydes and aldimines, giving the corresponding [alpha]-hydroxy and [alpha]-amino phosphonates with high enantioselectivity, respectively. The catalysis of the complex is attributed to its unique structure, where it has adopted a distorted trigonal bipyramidal configuration allowing the salalen ligand to take a cis-[beta]-like structure wherein the chiral amino group is located close to the metal center.

Chiral (nitrosyl)ruthenium(salen) complexes were found to be efficient catalysts for aerobic oxidative desymmetrization of meso-diols under photoirradiation to give optically active lactols. Spectroscopic analysis of the oxidation disclosed that irradiation of visible light is indispensable for dissociation of the nitrosyl ligand and also for single electron transfer from the alcohol-bound ruthenium ion to dioxygen.