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Chiral organic compounds in the photoexcited state are potential chiral luminophores. Photoluminescence properties of these compounds can be measured using circularly polarised luminescence (CPL) spectroscopy. Axially chiral binaphthyl BINAP in CHCl3 solution or the KBr-dispersed state exhibits no significant CPL signal. Herein, we report the first CPL spectrum of BINAP by doping into a poly(methyl methacrylate) (PMMA) organic polymeric matrix. For comparison, CPL data of BINAPO, a structural analogue of BINAP, were collected. Contrarily to BINAP, BINAPO showed a clear CPL signal in all three states.

Optically active α-aminoalkylphosphonic acids 1 are structural analogues of α-amino acids 2, obtained by isosteric substitution of the planar and less bulky carboxylic acid (CO2H) by a tetrahedral phosphonic acid functionality (PO3H2). Several α-aminoalkylphosphonic acids and derivatives have been isolated from natural sources, either as free amino acids or as constituents of more complex molecules. These classes of compounds are currently attracting interest in organic and medicinal chemistry, as well as in agriculture, due to their important biological and pharmacological properties. Additionally, the α-aminophosphonates have been used as key synthetic intermediates for the preparation of more complex compounds1b, and as organocatalysts., We gratefully acknowledge CONACyT of Mexico (grant 181816), Ministerio de Economía y Competitividad (grant CTQ2013-40855-R), and Gobierno de Aragón -FSE (research group E40).

We found that the combination of [Ir(cod)Cl] 2 and rac -BINAP served as an efficient catalyst for the [2+2+2] cycloaddition of 2,7-nonadiyne derivatives and related compounds with alkynyl ketones and alkynyl esters. The corresponding products were obtained in high yields under mild reaction conditions.

Cyclotrimerizations of ethynyl N-methyliminodiacetic acid (MIDA) boronate (1) with 1,6-diynes 2 have been studied, using three different catalysts (based on ruthenium, rhodium, and iridium) and variable reaction conditions. Successful cyclotrimerization reactions were obtained with both Cp*RuCl(cod) and Rh(cod)2BF4/BINAP as pre-catalysts in THF or acetone. Ruthenium-catalyzed cyclotrimerization of an unsymmetrically bromo-substituted diyne (2f) with 1 was successfully scaled up (2 g) and included in a total synthesis strategy toward potential selective inhibitors of tyrosine kinase 2.

A study on transition metal catalyzed alkyne cyclotrimerization of unsymmetrically bromo-substituted diynes with ethynyltrimethylsilane was carried out to prepare bicyclic bromobenzene key intermediates for the total synthesis of five potential tyrosine kinase 2 inhibitors. Two different pre-catalysts (Cp*RuCl(cod) and [Rh(cod)2]BF4/BINAP) and different reaction conditions have been examined.

A Rh-catalyzed diastereoselective reductive cyclization, mediated by hydrogen, of optically active 1,6-enynes using chiral BINAP was successfully applied to the total synthesis of four stereoisomers of the proposed structure of lucentamycin A. In order to synthesize two of these four stereoisomers, we successfully constructed chiral proline derivatives bearing cis -carbon substituents at C2 and C3 positions based on Krische’s methodology, which has very rarely been reported. Anti-proliferative activities on HCT-116 cell line and NMR data of these four stereoisomers were compared with those of naturally occurring lucentamycine A. The results show that the proposed structure of lucentamycin A needs revision.

Allylamine is one of the most fundamental units in organic chemistry which has been engineered to afford a diverse range of complex structural frameworks. This review encompasses the literature from 2006 to May 2010 concerning the utility of allylamine or substituted allylamines for the synthesis of aza-heterocycles. Reactions covered in this report include nucleophilic reactions, lactamizations, cycloadditions, free radical reactions, cross-couplings and reductive cyclizations. To limit the scope, however, ring-closing metatheses, Pauson-Khand reactions and cycloisomerizations are not included.

Convenient as well as convergent synthesis of functionalized tetrahydronaphthalenes has been accomplished under mild reaction conditions by the cationic rhodium(I)/H 8 -BINAP complex-catalyzed [2+2+2] cycloaddition of 1,7-octadiyne derivatives with functionalized monoynes. The effect of the diyne tether lengths was investigated, which revealed that 1,6-heptadiyne and 1,7-octadiyne exhibit higher reactivity than 1,8-nonadiyne. Mechanistic studies indicated that the present rhodium-catalyzed [2+2+2] cycloaddition proceeds through the rhodacyclopentadiene intermediate generated by oxidative coupling of a diyne with rhodium. On the other hand, in the reactions of diynes and dimethyl acetylenedicarboxylate, the rhodacyclopentadiene intermediate generated by oxidative coupling of a diyne and a monoyne with rhodium would also be involved.

A rhodium(I)-xylyl-BINAP catalyzed asymmetric [2 + 2 + 2] cycloaddition of achiral conjugated aryl ynamides with various diynes is described here. This asymmetric cycloaddition provides a series of structurally interesting chiral N,O-biaryls with excellent enantioselectivity along with a modest diastereoselectivity with respect to both C-C and C-N axial chirality.

A cationic rhodium(I)/BINAP complex catalyzes partial intramol. [2+2+2] cycloaddns. of 1,6- and 1,7-diynes with enol ethers or a ketene acetal giving substituted benzenes, e.g. I, in good yields. The same catalyst also catalyzes complete intermol. [2+2+2] cycloaddns. of two different monoynes with enol acetates giving tri- and tetrasubstituted benzenes, e.g. II, in good yields with complete regioselectivity. Com. available liq. enol ethers and acetates can be used as versatile equiv. for gaseous alkynes in the present rhodium-catalyzed formal cross-alkyne cyclotrimerizations. [on SciFinder(R)]

The combination of palladium chloride with BINAP shows high efficiency in the decarboxylative cross-coupling reactions of arenecarboxylic acids with aryl iodides. The reactions proceed smoothly to generate the corresponding biaryl compounds in good to excellent yields.

This review is intended to update the most recent developments in asymmetric hetero-Diels–Alder (HDA) reactions of carbonyl compounds, covering the literature from 2000 to 2008. The reactions of unactivated aldehydes, activated aldehydes, activated ketones and the inverse HDA reactions of α,β-unsaturated ketones and α,β-unsaturated aldehydes are successively investigated. This review clearly demonstrates the power of asymmetric HDA reactions of carbonyl compounds for the construction of chiral six-membered oxygen-containing heterocycles, with extensive synthetic applications in natural or unnatural products with a wide range of biological activity. Figure options Download full-size image Download as PowerPoint slide

A convenient one-step synthesis of chiral γ-lactones has been performed. The method is based on enantioselective hydrogenation of γ-ketoesters using the RuCl 3 –BINAP–HCl catalytic system. Chiral γ-lactones (91–99% ee) have been isolated in 57–88% yield.

A chirality-memorizing saddle-shaped porphyrin ( 1 2H ) with 3,5-dipyridylphenyl side arms at the opposite meso positions underwent supramolecular polymerization in CH 2 Cl 2 with a chiral Pd(II) complex of 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (Pd II (BINAP)), forming a ladder-shaped polymer ( 3 2H ) with a prevailing one-handed helical chirality. When this polymer was poured into AcOH containing 1,3-bis(diphenylphosphino)propane (DPPP) as a decomplexing agent, 3 2H was depolymerized in a stereochemically retentive way to give optically active 1 2H , hydrogen-bonded with AcOH. Although a cyclodimeric reference of 3 2H , formed from 2 2H having two 3-pyridylphenyl meso substituents in conjunction with Pd II (BINAP), behaved similar to 3 2H , the translation efficiency of helical chirality was lower than that in the case with 3 2H .

We have detd. that a cationic rhodium(I)/BINAP complex catalyzes a [2+2+2] cycloaddn. of 1,6-diynes with protected dehydroamino acids, leading to protected ﾎｱ-amino acids bearing a quaternary carbon center in high yield with high enantioselectivity. Thus, aminoisoindolecarboxylate I (Ts = tosyl) was obtained in 96% yield and 97 ee by cycloaddn. reaction of TsN(CH2C竕｡CMe)2 with AcNHC(:CH2)CO2Me using Rh(cod)2BF4/(R)-BINAP. [on SciFinder(R)]

The palladium-catalyzed monoamination of symmetric dibromobenzenes can be performed using a catalyst based on Pd2dba3 and BINAP in the presence of NaO(t-Bu). The analogous transformation of non-symmetric bromoiodobenzenes is most effectively performed with Xantphos as the ligand, while reactions with BINAP were non-selective. These transformations can be scaled uneventfully to >10 g quantities. They do not require drybox or Schlenk techniques, and all reagents are weighed out in air. The resulting monobromoanilines are versatile intermediates for further synthetic transformations.

Hydrogenation of (Z)-3-phenyl-2-butenoic acid with a Ru(CH3COO)2[(R)-binap] (BINAP=2,2′-bis(diphenylphosphino)-1,1′-binaphthyl) catalyst in methanol gives (S)-3-phenyl-2-butanoic acid and its R enantiomer in a 97:3 (4 atm) to 94:6 (100 atm) ratio in quantitative yield. Both hydrogen gas and protic methanol participate in the saturation of the olefinic bond. Analysis of the products obtained using (Z)-3-phenyl-2-butenoic acid-3-13C and either H2, a 1:1 H2–D2 mixture, or D2 in CH3OD indicates that several catalytic cycles are operative, showing different reactivity and stereoselectivity. The major S enantiomer was formed primarily by the standard Ru monohydride mechanism, whereas the minor R isomer is produced via more complicated routes.

Several Pd-catalyzed reactions were explored to further functionalize the bromo-substituted 4-amino-1,2,4,5-tetrahydro-2-benzazepin-3-one scaffold (Aba). We report in this paper suitable reaction conditions for Suzuki, Buchwald–Hartwig, and Heck reactions. The substitution pattern of the starting aminobenzazepinone turned out to be crucial for the success of these transition metal-catalyzed reactions, which often required modifications of standard literature procedures. The Pd-catalyzed methods provide access to novel substitution patterns of the Aba scaffold.

The mechanism of the asymmetric hydrogenation of 2-acyl-1-alkylidene-1,2,3,4-tetrahydroisoquinolines, the first reported reaction with the Noyori–Takaya Ru(CH3COO)2(binap) complex, has been investigated by means of deuterium labeling, kinetics, and NMR analysis. A series of experiments has revealed that (1) a monohydride-unsaturated mechanism operates involving the initial formation of RuH followed by reaction with the enamide substrate, (2) the hydride transfer from RuH to the olefinic double bond is endothermic and reversible, and (3) the rate is determined in the hydrogenolysis step. This view is consistent with that of proposed for the BINAP–Ru catalyzed Kagan reaction.

This report is intended to update the most recent advances in asymmetric synthesis using chiral sulfoxides, focusing on their use as chiral auxiliaries from 2000 to 2006 and their applications in the synthesis of biologically active products. The main purpose of this review is to demonstrate the growing potential of these chiral sulfur reagents in transmitting chirality to other centres, establishing the sulfinyl group as one of the most stereocontrolling elements in numerous asymmetric reactions. Figure options Download full-size image Download as PowerPoint slide

Asymmetric domino reactions are reviewed for the first time. The second part of the review includes asymmetric domino reactions catalysed by chiral catalysts and asymmetric biocatalysed domino reactions and covers the classification and characteristics of these asymmetric domino reactions, together with their most recent applications. This compilation clearly demonstrates the power and economical interest of asymmetric catalysed domino reactions in the field of synthetic organic chemistry including the asymmetric biocatalysed domino reactions.

We studied copper-free Sonogashira reaction using 7-chloro camptothecins, and determined that rac -BINAP/Pd(OAc) 2 was an efficient catalyst for the coupling reaction. With this process, a number of 7-substituted camptothecins with a wide range of functional groups are potentially accessible. Besides, two drugs, SN-38 and BNP-1350, could be prepared by this method.

A novel and practical synthesis of (R)- and (S)-muscones by the asymmetric hydrogenation of (E)- and (Z)-3-methyl-2-cyclopentadecen-1-ones catalyzed by p-tolyl-BINAP-Ru(II) complexes has been achieved in nearly complete enantioselectivity.

A variety of N-arylcyclopropylamines has been prepared in one step, by the Pd2(dba)3/BINAP/NaOtBu-catalyzed amination of an aryl bromide with cyclopropylamine. Compounds bearing the N-aryl substitutent (phenyl, 4-methylphenyl, 2-methoxyphenyl, 3-methoxyphenyl, 4-chlorophenyl, 1-napthyl, 9-anthryl, 9-phenanthryl, and 3-pyridyl) were prepared in isolated yields ranging from 43 to 99%. Overall, this chemistry represents a vast improvement over the previous multi-step procedures for the synthesis of compounds of this type.

Asymmetric cyclization using Rh-complexes was applied to the synthesis of 4,9-dimethylspiro[4.4]nonane-2,7-diones. The spiro[4.4]nonane skeleton bearing a chiral quaternary carbon could be stepwisely constructed by using Rh-catalyzed cyclization twice. All diastereomers of the spirodiketone could be stereoselectively prepared from the identical starting material by the combination of a neutral Rh(PPh3)3Cl and a cationic Rh[BINAP]ClO4. The cyclization by the neutral Rh(PPh3)3Cl proceeded to give cis-3,4-disubstituted cyclopentanones, while that by the cationic Rh[BINAP]ClO4 proceeded to afford trans-3,4-disubstituted cyclopentanones. Four spirodiketones of six stereoisomers could be prepared in optically active form, and the relationship between the stereochemistry of the spirodiketones and the Rh-complex was discussed based on the plausible acyl-hydride Rh-complexes.

The asymmetric isomerisation of 5,7-dibenzyloxy-6-(trialkylsilyloxy)cyclohepta-1,3-diene 1 to the corresponding 1,6-dibenzyloxy-7-(trialkylsilyloxy)cyclohepta-1,3-diene 2 can be accomplished at 90°C in a 75/25 mixture of toluene and DME in the presence of a [Rh(BIPNOR)(cod)] + catalyst with 92% ee. A much lower ee is observed with BINAP. In both cases, the observed ee's increase with temperature. A mechanism involving an η 5 -pentadienyl–rhodium complex is proposed.

BINAP/Ru(II) complexes catalyze enantioselective hydrogenation of sodium β-keto sulfonates in acidic methanol under atmospheric pressure of hydrogen at 50 °C to give the corresponding β-hydroxy sulfonates with up to 97% ee in a quantitative yield. The sense of asymmetric induction is predictable. The low-pressure hydrogenation process allows the hectogramscale synthesis of a variety of optically active β-hydroxy sulfonates, which attract attention in connection with their functions as surfactants, catalysts, enzyme inhibitors, etc.

Asymmetric hydrogenation of 3,5-dioxoesters 1a-c using Ru2Cl4((R) or (S)-binap)2(NEt3) as the catalyst gave dominantly anti 3,5-dihydroxyesters 2, which were then converted into unsaturated lactones 5a-b (ca. 80% e.e.). The pathway of the hydrogenation reaction was also investigated by asymmetric hydrogenation of (R)- or (S)-5-hydroxy-3-oxoester 8a-c. It was revealed that the Ru-binap catalyzed hydrogenation of 1a-b proceed dominantly via the β-diketone mode. A convenient asymmetric synthesis of hydroxylactone 3c and unsaturated lactone 5c was presented.

A series of raceme methyl α-[α-(methoxycarbonylamino)alkyl]acrylates ( 1a-e ) were hydrogenated using a variety ofRh(I) cationic complexes containing diphosphines and a chiral [Ru(OAc) 2 (S)-BIHAP] (BINAP = 2,2′-bis(diphenylphosphino)-1,1′-dinaphthyl) as catalyst precursors to give preferentially the threo isomers ( 2a-d ), the diastereoselectivity depending markedly on the alkyl group in 1 . In addition, the relative rate ratio, k R /k S , of a kinetic resolution during the Ru-catalyzed hydrogenation was found to be in a range 8–17, varying rather randomly as the alkyl group in 1 altered. The intercorrelation between the diastereoselectivity by virtue of the substrate-control and the kinetic discrimination of (±)- 1 arising from the chiral catalyst-control was discussed in one particular case.