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The indanyl core is ubiquitous in a large variety of drugs and natural products. Importantly, the ever-increasing demand for chiral catalysts bearing this scaffold calls for state of the art methods allowing for a step-economical enantioselective access to this structural motif. We herein summarize the asymmetric syntheses of indanes with a particular focus on asymmetric catalysis, covering the literature of the last decade until July 2015.

An efficient synthesis of novel dibenzofuran derivatives has been achieved via the Diels–Alder reaction of 1-(6-hydroxy-2-isopropenyl-1-benzofuran-yl)-1-ethanone, named euparin, with acetylenic diesters and propiolates in the presence of triphenylphosphine as a catalyst in toluene. All products were obtained by recrystallization from ethanol and did not require column chromatography.

A new method for the construction of chiral indenes bearing two stereogenic centers is developed.

An efficient and convenient synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives is described, using the electrogenerated anion of ethanol as the base in the presence of sodium bromide as an supporting electrolyte in a one-pot, three component condensation of malononitrile, aromatic aldehydes and 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one. The reaction is carried out in an undivided cell containing an iron electrode as the cathode and a graphite electrode as the anode, at a constant current at room temperature.

A novel NMO complex is discovered, which modulates the Standard Ley—Griffith oxidation such that benzylic and allylic alcohols are oxidized with considerable selectivity over primary and secondary alcohols.

A novel, simple, convenient, and efficient synthesis of the title compounds (IV) and (VII) via a metal-free, one-pot three component reaction procedure.

1-(Cyclohexylamino)-2-(aryl)pyrrolo[1,2-a]quinoline-3-carbonitrile derivatives were synthesized in an efficient method from four-component condensation reaction between cyclohexyl isocyanide, quinoline, malononitrile, and aromatic aldehydes in the presence of a catalytic amount of titanium dioxide (TiO2) in CH2Cl2 at ambient temperature in good yields. Silica gel column chromatography was employed for HCN elimination and then 1, 3 hydrogen shift was led to form final products 5a, 5b, 5c, 5d, 5e.

Hydrogen-atom transfer (HAT) counts amongst the most widely investigated routes to carbon-centered radicals. Intramolecular processes involving 1,5-HAT are widespread to promote regioselective radical "CH activation". The aim of this review is to draw up a comprehensive inventory of the less commonly encountered 1,n-radical translocations (n≠5) with the aim to update this topic with the most recent relevant data.

A simple and efficient pseudo eight-component synthesis of 1′,5′,7′,8′-tetrahydro-2′H,4′H-dispiro[[1,3]dioxane-5,3′-quinoline-6′,5″-[1″,3″]dioxane]-4,4″,6,6″-tetrone derivatives is described. This reaction between, aromatic aldehydes, aromatic amines and Meldrum's acid in the presence of benzoic acid as an efficient catalyst at ambient temperature affords the product in good yields.

Xylose is a natural, cheap, and efficient organocatalyst for the synthesis of the title compounds (V) (21 examples) via a four-component domino reaction between amines, dialkyl acetylenedicarboxylates, and formaldehyde.

The synthesis of chiral benzofulvenes, triggered by organocopper reagents, is achieved through a highly chemo-, regio-, diastereo-, and enantioselective bis(alkylating) cycloisomerization process.

Application of diethyl instead of dimethyl acetylenedicarboxylate furnishes the corresponding products in comparable yields.

A mild and efficient method for the synthesis of polysubstituted tetrahydropyridines has been developed which involves a three-component reaction of an arylamine (2 equiv.), an araldehyde (2 equiv.) and ethyl (or methyl) acetoacetate (1 equiv.) in MeCN under ambient conditions, in the presence of yttrium nitrate, Y(NO3)3·4H2O. This appears to be the first time yttrium nitrate has been used as a catalyst for this type of synthesis of tetrahydropyridines.

An efficient and straightforward procedure has been developed for the synthesis of highly substituted mono- and bis- N -aryl-3-aminodihydropyrrol-2-one-4-carboxylates via a one-pot, four-component domino reaction of amines, dialkyl acetylenedicarboxylates and formaldehyde in the presence of InCl 3 (20 mol%) in MeOH at ambient temperature. The salient advantages of this method are mild reaction conditions, environmentally benign, high to excellent yields, shorter reaction times, easy operation and no column chromatographic separation.

Maltose is a natural, economical and very effective catalyst for promotion of the four-component domino reaction between amines, dialkyl acetylenedicarboxylates and formaldehyde to afford substitut...

A facile one-pot synthesis of 3,4,5-substituted furan-2(5H)-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using tetra-n-butylammonium bisulfate as a catalyst has been developed.

Substrates, bearing axial chirality, can cyclize intra- or inter-molecularly with concomitant transfer of axial-to-central chirality to produce at least one stereocenter. In order to satisfy a strict definition of axial-to-central chirality transfer, the initial axial chirality must be lost during the cyclization process. Highly functionalized enantiopure carbocycles and heterocycles were prepared using this strategy. The transformations of configurationally stable substrates take place with high regio- and stereo-selectivity. Selected examples involving allenes, biaryls, arylamides and transient axially chiral short-lived species are discussed. Special attention is focused on the mechanistic rationale of the chirality transfer.

Saccharose is found to be an efficient and homogenous catalyst for the one-pot, three-component Mannich reaction of aromatic aldehydes (II), anilines (III), and acetophenone (I) at room temperature.

A simple and efficient method was developed for one-pot, five-component synthesis of highly functionalized piperidines from reactions of β-keto esters, aromatic aldehydes, and various amines catalyzed in acetic acid medium. The reaction proceeded smoothly to generate the corresponding product in good yield. We have found that the use of acetic acid as reaction medium has a remarkable beneficial effect on the reaction, allowing it to be performed without the need to incorporate a catalyst, which is the case in other similary reported methodologies. In all cases, the substituted piperidine precipitates out of solution.

A simple and efficient one-pot three-component reaction between hexamethyl phosphorous triamide and dimethyl acetylenedicarboxylate (DMAD) in the presence of CH-acids, such as acetylacetone, 1,3-indandione, dibenzoylmethane, anthrone, and N,N-dimethylbarbituric acid, has been studied. In all cases, new and stable phosphorus ylides are obtained in excellent yields. These stable ylides exist in solution as a mixture of two geometrical isomers as a result of restricted rotation around the carbon–carbon partial double bond, resulting from conjugation of the ylide moiety with the adjacent carbonyl group. From the reaction of N,N-dimethylbarbituric acid with DMAD in the presence of hexamethyl phosphorous triamide, a 1,4-diionic organophosphorus compound is obtained. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 24:84–89, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21067

A three-component synthesis of α-aminophosphonate is described from a reaction between aldehydes, 2-aminobenzothiazole, and triethyl phosphite in the presence of InCl3 as a catalyst under solvent-free conditions for the generation of the particular α-aminophosphonates. These products have two potentially biologically active parts, aminophosphonate and benzothiazole. This method offers advantages such as short reaction times, good yields, solvent-free conditions, and easy workup with the green aspects by avoiding toxic catalysts and solvents. The crystal structure of 4b has been determined by X-ray crystallography. This compound crystallizes in the monoclinic space group C2/c with cell parameters a = 21.9285(5) A, b = 10.3221(2) A, c = 18.5979(5) A, β = 108.759(3)°, V = 3985.99(18) A3, Dcalc = 1.301 mg m−3, and Z = 8. The final R value is 0.0501 for 3741 reflections. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 24:58–65, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21063

The addition of triphenylphosphine to acetylenedicarboxylic acid in the presence of N–H heterocyclic compounds such as carbazole, 2-indolinone, 2-benzoxazolinone, 2-mercaptobenzoxazole, 2,4-thiazolidinedione, benzimidazole, isatin, or saccharin leads to stable 1,5-diionic organophosphorus compounds in excellent yields at ambient temperature.

Highly substituted piperidines (IV) (23 examples) are obtained in a one-pot three-component synthesis from aromatic aldehydes, anilines, and β-ketoesters using the ionic liquid 1-methyl-2-oxopyrrolidinium hydrogensulfate as catalyst.

Addition of the acetylide (II) to tosylated α-amino esters allows the unexpected formation of desymmetrized diynes such as (III), (VI), and (IX) via stereoselective cleavage of one Tms group.

p-Toluenesulfonic acid monohydrate (p-TsOH·H2O) is a highly effective and efficient catalyst for the one-pot multicomponent coupling of aldehydes, amines, and β-ketoesters in EtOH at ambient temperature to give highly functionalized piperidines in high yields. This one-pot reaction has some important advantages such as the easy workup procedure, simple and readily available precursors, nontoxic and inexpensive catalyst, and good to high yields.

An efficient green protocol is described for the preparation of highly functionalized piperidines via a one-pot five-component reaction between aromatic aldehydes, anilines and β-ketoesters in the presence of oxalic acid dihydrate as catalyst in ethanol at ambient temperature. The structure as well as the relative stereochemistry of these compounds was confirmed by single X-ray crystallographic analysis.

Compounds (IV) and (VI) possess promising inhibiting activity in cell proliferation of MCF 7 and HEPG2 cells.

New and stable phosphorous ylides are obtained from a simple and efficient one-pot three-component reaction between hexamethyl phosphorous triamide and dimethyl acetylenedicarboxylate in the presence of NH-heterocyclic compounds in excellent yields at an ambient temperature. These stable ylides exist in solution as a mixture of two geometrical isomers as a result of the restricted rotation around the carbon–carbon partial double bond resulting from the conjugation of the ylide moiety with the adjacent carbonyl group. Dynamic effects are observed in the 1H NMR spectra that are attributed to the restricted rotation around the carbon–carbon double bond. The experimental rotational energy barrier (Δ G#) and other activation parameters on the basis of the 1H NMR study for the rotational interchangeable process of major and minor isomers in ylides 4a–dare reported. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:131–137, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20761

The tandem Crabbe homologation—radical rearrangement of terminal enediynes (I), (IV) and (VI) leads, in a one-pot procedure, to the enantioselective synthesis of six- and seven-membered ring α-aminoesters (III), (V), and (VII) bearing a quaternary stereocenter based on the phenomenon of memory of chirality.

A simple, efficient, and environmentally benign method has been developed for the synthesis of α-amino phosphonates. One-pot, three-component reaction of aldehyds, amines, and trialkylphosphite in the presence of silica-supported sodium hydrogen sulfate (NaHSO4-SiO2) as an inexpensive and reusable catalyst under solvent-free conditions at 80 °C affords the corresponding α-amino phosphonates in good yields and short reaction times.

The efficient, simple, and mild synthesis of the title compounds (IV) includes a very easy work-up procedure.

The reaction between electron-deficient acetylenedicarboxylates (I), triethyl phosphite (II), and N-H heterocycles (III) provides access to the stable phosphorus ylides (IV) in high yields.

The present procedure has the advantage that the reactions are performed under neutral conditions and that the substances can be mixed without any activation or modification.

Mesoporous silica grafted with a tertiary amine is used as a basic nanocatalyst to promote in confined medium the diastereoselective cascade rearrangement of enediynes (I), (IV), and (VII) based on the phenomenon of memory of chirality.

The reaction affords the products with excellent yields under mild conditions and does not require any prior activation.

The target compounds are prepared under mild conditions from benzaldehyde derivatives (I)/(VI), phenanthridine (II), isocyanides (III) and malononitrile (IV).

A diastereospecific synthesis of N-vinyl heterocyclic compounds is described from a reaction of dialkyl acetylenedicarboxylate and N-H heterocyclic compounds, such as phthalimide, saccharin, 3(2H)-pyridazinone, isatin, maleimide, 2,4-thiazolidinedione, 2-benzoxazolinione and 6-chloro-2-benzoxazolinione, in the presence of triphenylarsine as an efficient catalyst, in excellent yield. The presented one-pot method is simple and effective with mild conditions.