Tandem Intramolecular Hydroalkoxylation–Hydroarylation Reactions: Synthesis of Enantiopure Benzofused Cyclic Ethers from the Chiral Pool

Abstract

Anorganische Schichten: Graphenartiges MoS2 und WS2 wurde durch drei verschiedene chemische Methoden hergestellt. Mikroskopische Untersuchungen offenbarten, dass die Strukturen aus einer oder wenigen Schichten aufgebaut sind (siehe TEM‐Aufnahme von WS2‐Schichten), und ein atomar aufgelöstes TEM‐Bild zeigt, dass schichtförmiges MoS2 eine hexagonale Anordnung von Mo‐ und S‐Atomen aufweist (siehe Einschub).

Synthesis of Furoquinolines by a One‐Pot Multicomponent Cascade Reaction Catalyzed by Platinum Complexes

“…Protodemetallation of the latter affords the enol ether 7 and releases the catalytic species. [11] Once enol ether 7 is formed, it enters the second catalytic cycle. Thus, the coordination of the nitrogen atom of the imine 2 to the platinum catalyst forms 8 and favors the addition of the enol ether 7 to give the intermediate 9 through a Mannich-type process.…”

Synthesis of Spiroquinolines through a One‐Pot Multicatalytic and Multicomponent Cascade Reaction

“…More than ever, the industry demands from organic chemists the development of new strategies and technologies to obtain novel compounds in a fast, clean, and efficient way. Among these procedures are multicomponent reactions (MCRs) which offer the opportunity of building up complex molecules with exceptional synthetic efficiency, frequently with high stereoselectivity, from simple and easily available substrates.[1] Among MCRs, the Povarov reaction (the reaction of an aromatic imine and an activated olefin) provides a powerful method giving access to quinoline derivatives.[2] As a consequence of their relevant pharmacological profile, [3] the search for new methodologies to synthesize this kind of compounds is a research field of undoubted current attention.Following our interest in the development of new catalytic cascade reactions, [4] we considered the possibility of synthesizing functionalized quinolines in a single synthetic operation from alkynol, aldehyde, and aniline substrates (Scheme 1). Thus, we hypothesized that an intramolecular hydroalkoxylation reaction of alkynols 1, which is catalyzed by an appropriate metal complex, would provide exocyclic enol ethers 5.…”

“…[1] Among MCRs, the Povarov reaction (the reaction of an aromatic imine and an activated olefin) provides a powerful method giving access to quinoline derivatives. [2] As a consequence of their relevant pharmacological profile, [3] the search for new methodologies to synthesize this kind of compounds is a research field of undoubted current attention.Following our interest in the development of new catalytic cascade reactions, [4] we considered the possibility of synthesizing functionalized quinolines in a single synthetic operation from alkynol, aldehyde, and aniline substrates (Scheme 1). Thus, we hypothesized that an intramolecular hydroalkoxylation reaction of alkynols 1, which is catalyzed by an appropriate metal complex, would provide exocyclic enol ethers 5.…”

Gold‐Catalyzed Cascade Reactions of Alkynes for Construction of Polycyclic Compounds

“…In this case, the nucleophile for the second cyclization is the monosubstituted terminal alkene. A related cascade reaction terminated by Friedel‐Crafts type arylation was also reported by the same group 37. The Hashmi group succeeded in trapping the enol‐type intermediates with an external nucleophile (water or anilines), in the dual cascade reaction of diynyl diols 139 , to produce the highly rigid cage compounds 142 38,39.…”