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This Account describes our recent studies on the chemical synthesis of cyclic, densely substituted molecules by means of a hybrid approach consisting of the synergistic interaction between computational and experimental chemistry. In addition, two related total syntheses of complex molecules (±)-Scopadulin and (-)- Exiguolide are presented as case studies in which computational chemistry can be used to detect and, eventually, avoid potential failures involving key transformations of advanced intermediates. [ABSTRACT FROM AUTHOR]

An efficient,general, and atom-economic procedure for the synthesis of 2-amino-6 methyl-4-aryl-8-[(E)-arylmethylidene]-5, 6, 7, 8-4H-pyrano [3, 2-c]pyridine-3-carbonitriles has been developed by reaction of 3,5-bis[(E)-arylmethylidene]-tetrahydro-4(1H)-pyridinones with malononitrile. The reaction proceeds under green media (EtOH/H2O, 1:1) and in the presence of diammonium hydrogen phosphate (10%) or piperidine (10%) to afford pyranopyridines at room temperature with good high yields. [ABSTRACT FROM PUBLISHER]

An efficient procedure is described for ring-closing metathesis reactions. A conversion of 95 % for diethyl diallylmalonate in dilute solution could be achieved within a few minutes, reaching TOF=4173 min−1, with very low loading of commercially available Ru catalysts that contained unsaturated NHC ligands. In general, only 50 to 250 ppm of the catalyst is required to achieve near-quantitative conversion into a broad variety of 5-16-membered heterocyclic compounds. The practicality of this procedure was illustrated in the synthesis of 5-8-membered N- tert-butoxycarbonyl ( N-Boc)- and N- para-toluenesulfonyl ( N-Ts)-protected cyclic amines and 9-16-membered lactones. The synthesis of macrocyclic proline-based lactams required slightly higher catalyst loadings. Along with monocyclic products, oligomeric byproducts, mostly cyclodimers, were isolated and characterized. [ABSTRACT FROM AUTHOR]

The first total syntheses of Tectona grandis (teak) natural products hemitectol and tectol are described. The observation of spontaneous dimerisation of hemitectol to tectol suggests the monomer is the true natural product and that the dimer is an artifact of isolation. [ABSTRACT FROM AUTHOR]

A reasonably efficient two-step synthesis ofN-(2-ethylhexyl)-2,7-diiodocarbazole is presented. In the first step, the 4,4′-diiodobiphenyl was nitrated to a mixture of 4,4′-diiodo-2-nitrobiphenyl and 4-iodo-4′-nitrobiphenyl. In the second step, the mixture of these compounds was converted by simultaneous carbazole ring closure and N-alkylation to theN-(2-ethylhexyl)-2,7-diiodocarbazole by means of tris(2-ethylhexyl) phosphite. The synthesis represents a shorter alternative to the known more tedious procedures. The prepared compound is a suitable monomer for synthesis of conjugated polymers for optoelectronic applications. [ABSTRACT FROM PUBLISHER]

A practical synthesis of 3,4-dihydro-3-methyl-2H-1,3-benzothiazine-2-imine via intramolecular palladium-catalyzed C-S bond formation is presented and exemplified for both alkyl- and arylisothiocyanates. [ABSTRACT FROM AUTHOR]

A range of 1,7-diarylheptane-1,7-diones were electrooxidized in the presence of iodide ions and a base in a mixture of methanol and toluene as the reaction solvents to give the corresponding cyclized 1,2-diaroylcyclopentanes in moderate to good yields. The reactions were carried out under extremely mild reaction conditions for which the optimal amount of electrolytic current varied from 2.05-3.17 F.mol-1 depending on the substrates. The reaction presumably proceeds through a two-electron oxidation process in which the iodide ion plays an important role as the electron carrier. [ABSTRACT FROM AUTHOR]

A two-step sequence for the conversion of heterocyclic imines to saturated and unsaturated polycyclic chlorinated ∊-lactams is disclosed. In the first step, an acyl chloride addition followed by a substitution is used to achieve unsaturated methoxyamides. The final lactamization to two different classes of polycyclic ∊-lactams via formation of a C-C bond is realized by the use of metal chlorides as Lewis acid and as a source of chloride. The potential of the ∊-lactams in subsequent reactions is demonstrated by an elimination reaction. [ABSTRACT FROM AUTHOR]

The synthesis of the pseudopterosin A-F aglycone from 3-methylcatechol features (a) the use of asymmetric Ireland- Claisen and aryl Claisen rearrangements to install three of the four stereocentres present in the molecule and (b) an A→AB→ABC annulation strategy using ring-closing metathesis and cationic cyclisation reactions as the key steps. [ABSTRACT FROM AUTHOR]

A simple and general 'one-pot' procedure for the synthesis of 2,9-diarylpurines with one or multiple hydroxyl groups in the 2-aryl unit is described, from the reaction of 5-amino-4-amidinoimidazoles with phenolic aldehydes. [ABSTRACT FROM AUTHOR]

The synthesis of trisubstituted pyrrolidines and tetrahydrofurans from boronic acids, allenes, and imines or aldehydes via a five- and a three-step protocol, respectively, is described. The assignment of the relative stereochemistry in the pyrrolidines and tetrahydrofurans confirmed the mechanistically significant stereochemical divergence of the palladium-catalyzed three-component coupling reaction. The methodology is applicable to the preparation of combinatorial libraries of pyrrolidines related to pharmaceutical agents and bioactive natural products. [ABSTRACT FROM AUTHOR]

Diethyl 2-alkyl-2-(benzyloxycarbonylamino)malonates were saponified, activated with oxalyl chloride, and treated with primary aromatic amines. This gave 3,5-disubstituted hydantoin-5- carboxamides. As second products, 2-alkyl-2-formamido-N1,N3- bis(aryl)malonamides were isolated. The formation of both types of products is expected to include a cyclization to 2-alkoxyoxazol- 5(4H)-ones, acting as precursor for the hydantoins, or a further transformation to N-carboxy anhydrides, their chloride-promoted ring opening, and subsequent conversion to give the bis(aryl)malonamides [ABSTRACT FROM AUTHOR]

This Account describes our work on highly electrophilic γ-carbonyl cations featuring propargyldicobalt cations, cycloheptynedicobalt complexes, and the interconnection between the two systems. [ABSTRACT FROM AUTHOR]

Abstract: A simple and efficient method for the synthesis of 2-(2-acylvinyl)-3-(5-alkyl-2-furyl)indoles by reductive recyclization of bis(5-alkyl-2-furyl)(2-nitroaryl)methanes is reported. This transformation was carried out by heating the substrates with SnCl2·2H2O in ethanol. The intermediate nitrosoarene moiety interacted with the furan ring via electrophilic nitrogen attack onto the C(2) position of the furan ring. It was shown that the related bis(5-alkyl-2-thienyl)(2-nitroaryl)methanes under the same reaction conditions failed to undergo the analogous recyclization and were transformed into bis(5-alkyl-2-thienyl)(2-aminoaryl)methanes. [Copyright &y& Elsevier]

A synthetic strategy based on the sequential application of an aromatic aza-Claisen rearrangement and an intramolecular Heck reaction as the key steps has been developed for the synthesis of various new coumarin- and quinolone-annulated benzazocinone derivatives in 60-70% yields. [ABSTRACT FROM AUTHOR]

A variety of 3-arylated di- and tetrahydro-2H-2-benzazepin- 1-ones were efficiently assembled through a sequence involving a Suzuki-Miyaura cross-coupling reaction with enol phosphates derived from the corresponding benzazepine-1,3-diones. This technique has been further exploited for the construction of the homoprotoberberine skeleton, which was readily accessed by intramolecular carbocationic annulation reaction applied to a suitably substituted precursor. [ABSTRACT FROM AUTHOR]

Benzo-condensed four-ring heterocycles, such as benzoxetes 1 and benzothietes 3 represent multi-purpose starting compounds for the preparation of various higher heterocyclic ring systems. The thermal or photochemical valence isomerizations between the benzenoid forms 1,3 and the higher reactive o-quinoid structures 2,4 provide the basis for the synthetic applications. On the other hand, this valence isomerization impedes in particular the generation and storage of 1 because the thermal equilibrium 1⇆ 2 is completely on the side of 2. Thus, the number of erroneous or questionable benzoxete structures published to date is surprisingly high. On the contrary, the thermal equilibrium 3⇆4 is on the side of the benzothietes 3, which makes them easily accessible, especially by different flash vacuum pyrolysis techniques. The present article gives a survey of the preparations of 1 and 2, and tries to stimulate their use in synthetic projects. Naphtho-condensed and higher condensed compounds and compounds with an exocyclic C=O or S=O double bond (lactones, thiolactones, sulfoxides and sulfones) are not covered in this article. [ABSTRACT FROM AUTHOR]

A new synthesis to bis-butenolide derivatives from inexpensive divinylglycol is described, employing a sequential double acylation followed by a double ring-closing metathesis. The selectivity is affected by the choice of catalyst. [ABSTRACT FROM AUTHOR]

The N-alkylated 2,2,6,6-tetramethylpiperidin-4-ones 3c-f were prepared from the acetal 6a of triacetonamine (3a) by alkylation followed by hydrolysis of the acetal functionality or alternatively from the corresponding secondary alcohol 2,2,6,6-tetramethylpiperidin-4-ol (7a) by N-alkylation and subsequent oxidation to introduce the ketone unit. Direct alkylation of 3a was only possible by using highly reactive halides such as allyl or benzyl bromide with low yields. Treatment of phorone (5) with primary amines 2c-f with an alkyl group greater than methyl did not lead to the desired heterocycles 3c-f since open-chain addition products 8 and 9 were formed instead. Consequently, the reactions of acetone (1) with benzyl- or n-butylamine (2e,f) in the presence of calcium chloride did not generate the corresponding N-alkylated derivatives of 3a. [ABSTRACT FROM AUTHOR]

A new method for the synthesis of pyrrolo[1,2- d][1,4]benzodiazepines is described. The method is based on the acid-catalyzed recyclization of N-[2-(5-alkyl-2-furyl)phenyl]-2- aminoacetamides and permits the formation of both diazepine and pyrrole rings in one pot. The reaction proceeds via furan ring opening to give the diketone moiety followed by consecutive reactions of the free amino group with both carbonyl functions. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations of several 2-X-substituted phenyl cations (X = 2-CHO, 2-CH2OH, 2-CHS, 2-CHNH, 2-OCHNH, 2-SCHNH, 2-CHCH–CHCH2, 2-CHCH2 and 2-NO2) have been carried out in the gas phase and in acetonitrile (MeCN) at the B3LYP/6-31G(d,p) level of theory. The stationary point geometry of these aryl cations have been found to be in strong dependency of the medium. In the gas phase, unexpected behavior of considered aryl cations takes place resulting in the rearrangement or ring closure reaction. Such the cyclization reaction is proceeding via the nearby atom of the substituent which appears in relative vicinity (up to ∼3 Å) to the cationic center. Only in the case of 2-NO2 derivative, the geometry optimization has lead to rearranged quazi-quinoid structure of the cation that, obviously, takes place because of instability of the ring formed. Scan of the potential energy surface (PES) of 2-nitrophenyl cation has displayed no any reaction path leading toward the rearranged structure. Thus, the impossibility of existing of the singlet state of 2-nitrophenyl cation in the gas phase has been offered. The singlet–triplet transition of 2-nitrophenyl cation has been discussed in terms of the spin–orbit coupling (SOC) effects. [ABSTRACT FROM AUTHOR]

Cascade cyclization of bromoenynes bearing an aryl group with catalytic amounts of palladium(II) acetate and cesium carbonate led to the direct construction of tri- or tetracyclic heterocycles. Direct arylation of a pyrrole, furan or thiophene ring in the cascade reaction affords the corresponding fused heteroarenes in moderate to good yields. [ABSTRACT FROM AUTHOR]

new approach to highly functionalized quinolines is proposed. This approach is based on the electrophilic recyclization of 2-[2-(acylamino)benzyl]furans under the Bischler-Napieralski reaction conditions. [ABSTRACT FROM AUTHOR]

When the PADAM (Passerini reaction-amine deprotection- acyl migration) strategy is applied to N-Boc amino acids, the resulting β-acylamino-α-hydroxyamides can be elaborated by secondary- alcohol oxidation, Boc deprotection, and intramolecular cyclisation. When TFA is employed to cleave the Boc group a spontaneous aromatisation to 2(1H)-pyrazinones is observed. [ABSTRACT FROM AUTHOR]

The Groebke-Blackburn transformation of an 3-aminopyridazine, a benzaldehyde, and an isocyanide allows the onestep assembly of so far unknown 3-amino-2-arylimidazo[1,2-b]-pyridazines. Diversely substituted aldehydes and isocyanides can be used for this reliable three-component condensation, delivering biheterocyclic products with a broad range of different substituents in the imidazole moiety. [ABSTRACT FROM AUTHOR]

An improved two-step synthetic approach towards 3-(2-chloroethyl)cyclobutanone is described and used in the synthesis of a class of 2-alkyl-2-azabicyclo[3.1.1]heptane-1-carbonitriles. The key step consists of a reversible addition of hydrogen cyanide onto the in situ generated imines, followed by an intramolecular nucleophilic substitution, thereby leading to the bicyclic skeleton in moderate to good yields (47-92%). These bicyclic compounds are stable, and the incorporated cyano group can be easily reduced to the corresponding aminomethyl group in high yields (93-99%), using lithium aluminum hydride. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of a series of benzo(iso)quinoline and phenanthroline derivatives has been achieved using an efficient one-pot procedure. It proceeds through a Suzuki–Miyaura cross-coupling followed by a Dieckmann–Thorpe ring closure under microwave irradiation and provides easy access to building blocks not readily available through other methods. [Copyright &y& Elsevier]

In this paper, a novel route for the synthesis of (+)- (1R,3S)-cis-chrysanthemic acid is described. The use of readily available (-)-D-pantolactone as a starting point, application of ringclosing metathesis to form the cyclopentene intermediate, and Haller-Bauer/Grob-type fragmentation to form the target compound are the highlights of the present synthesis. [ABSTRACT FROM AUTHOR]

This review highlights advances in the synthesis of morphan compounds from 1980 to the present day. [ABSTRACT FROM AUTHOR]

An efficient access for the synthesis of substituted pyrazino[2',3':4,5]thieno[3,2-d]pyrimidines and pyrazino[2',3':4,5]thieno[3,2-d]-1,2,3-triazines, heteroaromatic nitrogen ligands, is reported. The title compounds were obtained by functionalization of the corresponding chloro precursors, synthesized by reaction between 7-aminothieno[2,3-b]pyrazine-6-carbonitrile and N,N-dimethyldichloromethyleniminium chloride (Viehe's salt) or sodium nitrite/hydrochloric acid, respectively. Moreover, this procedure provided a convenient synthetic route to bis(pyrazino[ 2',3':4,5]thieno[3,2-d]pyrimidines), functionalized molecules that are not readily available by other synthetic methods. [ABSTRACT FROM AUTHOR]

A series of diversely substituted 2H-2-benzazepine-1,3- diones were efficiently prepared from the unsaturated precursors, N-acyl-o-vinylbenzamides, through a ring-closing metathesis reaction. The parent compounds were easily obtained from the appropriate o-vinylbenzoic acids. [ABSTRACT FROM AUTHOR]

A highly convergent, stereoselective total synthesis of a ten-membered lactone, stagonolide G, is described. Epoxide ringopening with vinyl Grignard, Yamaguchi esterification and ringclosing metathesis are the key steps involved in the present approach. D-Mannitol was used as a chiral pool material for the construction of both of the key fragments – the olefinic acid and the olefinic alcohol moieties. [ABSTRACT FROM AUTHOR]

An asymmetric synthesis of di- and trisubstituted cyclopropanes proceeding through an intramolecular ring closure of activated chiral benzyl alcohols has been developed. The chiral alcohol intermediates are obtained from asymmetric reduction of readily available 1,4-keto esters and undergo a one-pot activation and ring closure to provide the ester-functionalized cyclopropanes in high enantio- and diastereomeric purity. This methodology avoids the use of hazardous diazo and alkyl zinc reagents commonly employed in cyclopropanation reactions. [ABSTRACT FROM AUTHOR]

A series of 2,6,9-substituted adenines were obtained from the easily accessible 5-amino-4-cyanoformimidoyl imidazoles, acetic and benzoic anhydrides, and primary alkyl amines in a three-step sequence. Acylation of 5-amino-4-cyanoformimidoyl imidazoles followed by addition of the amine led to the intermediates 5-amino-4-(N-acyl)formamidino imidazoles under mild conditions. Cyclization of 5-amino-4-(N-acyl)formamidino imidazoles under reflux in ethanol led to the desired substituted adenine. A preliminary stepwise study led to the development of three general and efficient one-pot methods for the synthesis of adenine derivatives. The one-pot, three-step reaction in the presence of DMAP was the most convenient synthetic approach. [ABSTRACT FROM AUTHOR]

A series of 2,6,9-substituted adenines were obtained from the easily accessible 5-amino-4-cyanoformimidoyl imidazoles, acetic and benzoic anhydrides, and primary alkyl amines in a three-step sequence. Acylation of 5-amino-4-cyanoformimidoyl imidazoles followed by addition of the amine led to the intermediates 5-amino-4-(N-acyl)formamidino imidazoles under mild conditions. Cyclization of 5-amino-4-(N-acyl)formamidino imidazoles under reflux in ethanol led to the desired substituted adenine. A preliminary stepwise study led to the development of three general and efficient one-pot methods for the synthesis of adenine derivatives. The one-pot, three-step reaction in the presence of DMAP was the most convenient synthetic approach. [ABSTRACT FROM AUTHOR]

1-Silaindenes are prepared starting from (2-vinylphenyl)hydrosilanes and alkynes through a ruthenium-catalyzed hydrosilylation-ring-closing-metathesis sequence. The method is successfully applied to the synthesis of molecules containing multiple silaindene units. [ABSTRACT FROM AUTHOR]

5-(5-Aminoimidazol-4-yl)-1,2,4-triazol-3-ones were obtained under mild experimental conditions from 5-amino-4-(N-ethoxycarbonyl) cyanoformimidoyl imidazoles and hydrazine in a rapid one-pot reaction. When hydroxylamine hydrochloride was used, in the presence of base, the corresponding 1,2,4-oxadiazol-5-ones were isolated. An equally fast reaction occurred when 5-amino-4-(N-acetyl/benzoyl) cyanoformimidoyl imidazoles were combined with hydrazine to give 5-(5-aminoimidazol-4-yl)-1,2,4-triazoles. [ABSTRACT FROM AUTHOR]

Abstract: A straightforward, two-step synthesis of fluoro substituted chromeno[2,3-c]pyrazol- and [1]benzothieno[2′,3′:5,6]pyrano[2,3-c]pyrazol-4(1H)-ones, respectively, is presented. Hence, treatment of 1-substituted or 1,3-disubstituted 2-pyrazolin-5-ones with fluoro substituted 2-fluorobenzoyl chlorides or 3-chloro-6-fluoro-1-benzothiophene-2-carbonyl chloride using calcium hydroxide in refluxing 1,4-dioxane gave the corresponding 4-aroylpyrazol-5-ols, which were cyclized into the fused ring systems. 5-Fluorochromeno[2,3-c]pyrazol-4(1H)-one was obtained upon treatment of the 1-(4-methoxybenzyl) protected congener with trifluoroacetic acid. Treatment of 5-fluorochromeno[2,3-c]pyrazol-4(1H)-ones with methylhydrazine afforded novel tetracyclic ring systems such as 2-methyl-7-phenyl-2,7-dihydropyrazolo[4′,3′:5,6]pyrano[4,3,2-cd]indazole. Detailed NMR spectroscopic investigations (1H, 13C, 15N, 19F) with the obtained compounds were undertaken. [ABSTRACT FROM AUTHOR]

A facile synthesis of the core cycloisodityrosine 14-membered ring system is detailed from commercially available L-tyrosine through a novel synthetic approach to aryl boronic acid 12 via intramolecular cyclization. [ABSTRACT FROM AUTHOR]

Abstract: The regiochemistry of nucleophilic substitution of 4-phenylsulfonyl tetrafluoropyridine with unequal bidentate nucleophiles was investigated. The first nucleophilic substitution occurs at the 2-position of the pyridine ring by nitrogen nucleophile site (secondary or primary amine) followed by intermolecular ring closure at the geometrically accessible 3-position of the pyridine ring (by S, O and N nucleophiles). From this investigation, difluorinated tetrahydropyrido[3,4-b][1,4]oxazine, thiazine and pyrazine scaffolds were synthesized very readily by a one-pot annelation reaction of 4-phenylsulfonyl tetrafluoropyridine with appropriate unequal bidentate nucleophiles. [Copyright &y& Elsevier]

Treatment of 2-alkylidenecycloalkanones with hydrogen iodide in benzene and subsequent reaction of the obtained β-iodo ketones with zinc dust in THF in the presence of chlorotrimethyl�silane or titanium(IV) chlorotriisopropoxide led to exo- and endo-(n+3)-alkylbicyclo[n.1.0]alkan-1-ols in high yields. Cyclization of the intermediate β-iodo ketones under these conditions proceeded in a moderate to good diastereoselectivity, and the resulted bicyclic cyclopropanols were easily separated by column chromatography over silica gel. exo-7-Isopropylbicyclo[4.1.0]heptan-1-ol obtained in this manner was efficiently employed as a key intermediate in the synthesis of capsaicin. [ABSTRACT FROM AUTHOR]

Abstract: A one-pot synthesis of novel poly-substituted phenanthrenes is described in this article through a Suzuki–Miyaura cross-coupling followed by a Dieckmann–Thorpe ring closure under microwave irradiation. The selection of the appropriate starting materials allowed us to introduce diversity on various positions of the phenanthrene ring system. [Copyright &y& Elsevier]

Annulated analogues of 5,6-dihydroxypyrimidine-4-carboxylate ester and 5,6-dihydroxypyrimidine-4-carboxylamide were synthesized. The intermediary homoallylic amines were subjected to a ring-closure reaction under different reaction conditions. A notable pH-dependency of the ring closure leading to regioisomeric tetrahydropyrrolo[1,2-a]pyrimidines was observed. Treatment with dimethyldioxirane and base led to 3-hydroxy-4-oxo-4,6,7,8-tetrahydropyrrolo[1,2-a]pyrimidines while m-chloroperbenzoic acid or NBS afforded 3-hydroxy-2-oxo-2,6,7,8-tetrahydropyrrolo[1,2-a]pyrimidines. [ABSTRACT FROM AUTHOR]

Abstract: A simple and convenient route is presented for the preparation of regio- and stereoisomers of novel azepane β-amino esters, starting from bicyclic β-lactam isomers. The synthetic procedure consists of dihydroxylation of the olefinic bond of the alicyclic amino esters, followed by NaIO4-mediated cleavage of the diol intermediate and reductive ring closure, which furnishes novel regioisomeric 5-aminoazepane-4-carboxylate and 3-aminoazepane-4-carboxylates. This method also allows the preparation of amino esters with an azepane skeleton in enantiomerically pure form. [Copyright &y& Elsevier]

Novel azabicyclic β-amino acid derivatives were readily prepared from diexo or diendo norbornene β-amino acids. The 3-azabicyclo[3.2.1]octane skeleton was obtained by NaIO4-mediated cleavage of the dihydroxylated β-amino ester intermediates, followed by reductive amination. Lipase-catalyzed enantioselective ring opening of racemic exo-norbornene β-lactam allowed preparation of the corresponding azabicyclic exo β-amino acid in enantiopure form. [ABSTRACT FROM AUTHOR]

Abstract: An efficient synthesis of 9,10-disubstituted phenanthrenes is described in this Letter. These novel useful building blocks were obtained in a one-pot reaction including Suzuki–Miyaura cross-coupling followed by a Dieckmann–Thorpe ring closure under microwave irradiation. The selection of the appropriate reagents and the optimal reaction conditions to isolate the intermediate biphenyl compound or the final substituted phenanthrenes in high yields will be discussed in this Letter. [Copyright &y& Elsevier]

The synthesis of previously unreported 1-amino-6,7-dihydro-7-(hydroxymethyl)-4-nitropyrrolo[1,2-f]pyrimidin-3-(5H)-one starting from 2-amino-6-methylpyrimidin-3-one is described. [ABSTRACT FROM AUTHOR]

Chiral (RS,R)- and (RS,S)-N-(tert-butylsulfinyl)-2-aryl-aziridines were transformed into (R)- and (S)-2-aryl-1-benzylaziridines via a short three-step procedure. Deprotection and ring opening of (RS,R)- and (RS,S)-N-sulfinyl-2-arylaziridines (95-99% de) in acid medium afforded 2-aryl-2-chloroethylamine hydrochlorides in high yield (83-90%). These intermediates were converted into the corresponding chiral N-(benzylidene)-β-aryl-β-chloro-amines in good yield (78-85%). Subsequent reduction of the synthesized ald�imines afforded chiral 2-aryl-1-benzylaziridines in good to excellent yield (74-94%) and enantiomeric excess (83-99% ee). The enantiomeric purity of the chiral aldimines and aziridines was established by NMR spectroscopy using Pirkle alcohol as the chiral solvating agent. [ABSTRACT FROM AUTHOR]

Abstract: A convenient synthesis of 3-arylbenzo[b]thiophenes utilizing an interrupted Pummerer reaction of 2-(1-arylvinyl)phenyl ethyl sulfoxides is described. Thus, treatment of these sulfoxides, which were readily prepared from 2-sulfanylphenyl ketones or 2-fluoro-5-methoxybenzaldehyde, with acetic anhydride at 100°C afforded 3-arylbenzo[b]thiophenes in reasonable yields. [Copyright &y& Elsevier]