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3-alkylated anisole compounds of pentaammineosmium(II) were treated with methyl vinyl ketone and triflic acid to form 4H-anisolium Michael adducts, which deprotonate regioselectively at the benzylic position next to C3, after which they undergo an aldol cyclization. The dienonium product reduction can be directed in 1,4 way to provide a trans decalin, or in a 1,2 way to provide methoxydiene.

Complexation of an arene by an electron-deficient transition metal center has been much researched over the past 30 years. Anisoles were complexed by pentaammineosmium(II) and the result 5,6-eta2-anisole compounds were treated with activated olefins or acetals, forming 4H-anisolium compounds. They were able to undergo inter or intramolecular nucleophilic addition reactions, and 2-methoxy-1,3-cyclohexadiene complexes were formed. These can be readily converted into functionalized cyclohexenones, cyclohexadienes, and cyclohexenes.

A study was conducted on the reaction of the complex of [Os(NH3)5(eta2-anisole)]2+ with acetals or Michael acceptors to produce 4-methoxystyrene complexes that are exclusively coordinated at the arene (eta2). These styrene complexes are active dienes and are involved in Diels-Adler reactions with electron-deficient olefins to form tetrahydronaphthalene complexes. The cycloadducts are produced as single diastereomers and are essential as precursors to functionalized tetralins and decalins.

An experiment evaluated the basic transmutations of eta2-coordinated furan complexes of pentaammineosmium(II). Coordination of the electron-rich pentaammineosmium(II) moiety to a furan significantly changes the structural and chemical character of the ligand, with the generated complexed ligands easily experiencing different electrophilic addition reactions that feature two reactive species. These species are the apparently interchangeable open-chain eta2-vinyl cation species and eta2-3H-furanium species.

The methodology for the vicinal difunctionalization of furan due to eta(super 2) complexation of furan with a transition metal is extended for heterocyclic synthesis. An eta(super 2)-furan complex containing osmium reacts with different electrophiles and the reactivities are compared. ORTEP diagrams reveal the distortion in the furan ligand which resembles a vinyl ether due to metal binding. Furan loses its aromaticity due to complexation.

Presents a study that prepared a series of the form [Os{NH3)5(4,5,-...-L)]2+ where L = furan and various alkylated furans. Surveying of heterocycle complexes; Methodology utilized in the study; Results and conclusions of the study.

Focuses on the treatment of the 3-alkylated anisole complexes of pentaammineosmium(II) with methyl vinyl ketone and triflic acid in forming the 4H-anisolium Michael adducts. Deprotonate regioselectivity of these compounds; Directing of the reduction of the dienonium product; Reference to the addition reactions experienced by arene complexes of pentaammineosmium(II).

Examines how the pentaammineosmium(II) is responsible for complexing a series of anisoles, while highlighting the treatment with activated olefins or acetals in the presence of triflic acid in the formation of the 4H-anisolium complexes. Capabilities of these intermediates; Conversion of complexes; Modification of the arene reactivity.

Presents a study which focused on the use of Diels-Alder cycloaddition of a styrene and olefin in decalin formation. Information on styrenes participation in cycloaddition; Details on the experiments conducted; What these experiments revealed; Information on the cycloaddition between styrenes and dienophiles.

Studies the chromium-mediated asymmetric synthesis of both enantiomers of acetoxytubipofuran. Key issues of interest; Analysis of pertinent topics and relevant issues; Implications on biochemistry.