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The synthesis of cyclohepta[b]indole derivatives through the dearomative (4 + 3) cycloaddition reaction of 2-vinylindoles or 4H-furo[3,2-b]indoles with in situ generated oxyallyl cations is reported. Oxyallyl cations are generated from α-bromoketones in the presence of a base and a perfluorinated solvent. Cyclohepta[b]indole scaffolds are obtained under mild reaction conditions, in the absence of expensive catalysts, starting from simple reagents, in good to excellent yields and with complete diasteroselectivity. Preliminary expansion of the scope to 3-vinylindoles and to aza-oxyallyl cations is reported.

Merging the ability of cationic gold(I) catalysts to activate unsaturated π-systems with the electrophiles-driven ring-opening reactions of furans, we describe a new approach to synthesize 2-spiroindolin-3-ones from 4H-furo[3,2-b]indoles. The reaction occurs through a cascade sequence involving addition of a gold-activated allene to the furan moiety of the starting furoindole followed by a ring-opening/ring-closing event affording 2-spirocyclopentane-1,2-dihydro-3H-indolin-3-ones in moderate to good yields.

The synthesis of 3substituted 1methylpyrrolo[1,2a]pyrazines and 3substituted isoquinolines was achieved by the intramolecular cyclisation of 2acetyl1propargylpyrroles and 2alkynylbenzaldehydes, respectively, in the presence of ammonia under microwave heating. The tandem iminationannulation of 2alkynylbenzaldehydes was easily accomplished under standard conditions, while TiCl4was used to achieve pyrrolo[1,2a]pyrazines. The reaction mechanism and the regioselectivity were discussed on the basis of theoretical calculations and spectroscopic data. © WileyVCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009

2AcylNpropargylindoles 1and 2acyl3propargylindoles 5undergo aminobenzannulation reactions with pyrrolidine in the presence of an appropriate Lewis acid to give 9aminopyrido[1,2a]indoles 6and 1aminocarbazoles 7, respectively. The selection of the appropriate Lewis acid, TiCl4or GaCl3for 1and InCl3for 5, allows the domino process involving the initial formation of an enamine intermediate, followed by a regioselective 6exodigintramolecular nucleophilic attack of the nucleophilic terminus of the unsaturated system the βcarbon of the enamino moiety to the carbon–carbon triple bond. Moreover, several features concerning the reaction mechanism and the role of both catalysts, in connection with the electronic properties of the reacting alkynes, are reported. © WileyVCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009

The reaction of β‐(2‐aminophenyl) α,β‐ynones with N‐methyl nitrones provides a simple and efficient entry to the isoxazolino[4,5‐c]quinoline ring system through a sequential 1,3‐dipolar cycloaddition/annulation process. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

The synthesis of diastereoisomeric 3,4-disubstituted 1,2,3,4-tetrahydrocarbazoles by Diels–Alder cycloaddition reactions between [(E)-2-vinyl]indole-1-carboxylic acid ethyl esters and open-chain C=C dienophiles is reported and discussed. The reactions proceed with high regioselectivity whereas the diastereoselectivity ranges from moderate to excellent depending on the substitution pattern on both the dienes and dienophiles and on the catalyst employed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

An original TiCl4/t-BuNH2-mediated hydroamination/annulation domino reaction of -keto-acetylenes is described. The synthesis of pyrrolo1,2-aindole-2-carbaldehydes, starting from 2-carbonyl-1-propargyl-1H-indoles runs under mild reaction conditions. A conceivable mechanism is also discussed. TiCl4has proved to be an effective multiactivity reagent:  catalyst/Lewis acid/water scavenger. Some unpublished 2-carbonyl-1-propargyl-1H-indoles are prepared by means of Suzuki- and Negishi-type reactions.

The intramolecular Pd(II)-mediated cyclization of 1-allyl-2-indolecarboxamides leads to pyrazino[1,2- A]indoles through the conversion of the olefinic C-H bond into a C-N bond by reaction with an amide group. When operating on the allylamide, a domino process was observed with a double C-H functionalization.

β-(2-Aminophenyl)-α,β-ynones react with nitrile oxides by domino [3+2] cycloaddition/annulation reactions giving rise to isoxazolo[4,5-c]quinolines in satisfactory yields. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

3-(2-Amino-5-methylpyridin-3-yl)-1-arylprop-2-yn-1-ones 2, readily available through Pd-catalyzed carbonylative coupling of 5-methyl-3-[2-(trimethylsilyl)ethynyl]pyridine-2-ylamine (1) with aryl iodides in the presence of carbon monoxide, undergo a domino conjugate addition/annulation reaction to give 4-heterosubstituted 2-aryl[1,8]naphthyridines 3 in high yields.

2-Acyl-1-benzenesulfonyl-3-iodo-1H-indoles and 1-benzenesulfonyl-3-iodo-1H-indole-2-carbaldehyde give in satisfactory yields 1,3- and 3-substituted-β-carbolines, respectively, by combined palladium-catalyzed coupling with alk-1-ynes followed by 6-endo-dig cycloamination reactions.

The base-promoted reactions of easily accessible α-aminohydrazones represent a simple and efficient method for the preparation of both 1-substituted and 1-unsubstituted-4-aminocarbonyl-1H-pyrazol-5(2H)-ones, whereas the copper promoted reactions provide a divergent facile regiocontrolled synthesis of the imidazoline/imidazole ring system. The copper-promoted reaction of the α-benzylaminohydrazone produces a 2-oxo-1,4-diazadiene derivative. Finally, the imidazolines can be easily hydrolyzed to α-ketohydrazones.

No Abstract Supporting information for this article is available on the WWW under http://www.angewandte.com or from the author.

Stereoselective dominos: Cascade reactions of easily accessible α‐propargylaminohydrazones 1represent a simple and efficient method for the preparation of pyrazolones 3.

Silver triflate is the catalyst of choice for the microwave‐promoted domino nucleophilic addition/annulation reaction of a variety of 2‐alkynyl‐acetophenones (I) and acetyl‐2‐alkynylpyridines (IV) in the presence of ammonia.

A small library is prepared by three‐component reaction of propargylic alcohols with cyclic amines and 2‐acetylindole.

The microwave‐assisted domino addition—annulation reaction of o‐bromobenzaldehydes (I) and (VIII) with terminal alkynes (II), (V), (IX) and methanol is successfully transformed to a direct multicomponent approach.

An unprecedented multicomponent synthesis of isoquinolines (III) and related 1,6‐naphthyridine (V) is developed.

The sequential transformation of ortho‐alkynylbenzaldehydes in the presence of methanol proceeds generally with high regio‐ and stereoselectivity to provide the target compounds with (Z)‐configuration at the exocyclic double bond.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.