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The first umpolung addition/intramolecular Wittig reaction, catalytic in phosphine, is described. The in situ phosphine oxide reduction was accomplished by the use of silane and a catalytic amount of bis(4-nitrophenyl)phosphate. This catalytic protocol is applicable to the synthesis of a wide range of functionalized 9H-pyrrolo[1,2-a]indoles and pyrrolizines (18 examples, 70–98% yields).

An original and rapid domino reaction for access to oxazolidin-4-ones is presented. Simply by heating α-bromoamido alcohol in the presence of KNaCO3 and water with readily prepared Michael acceptors, an unprecedented molecular rearrangement is generated. This new methodology enables the hitherto unreported synthesis of functionalized oxazolidin-4-ones. The process was proved to be compatible with a wide variety of substrates, and high regioselectivities were achieved.

A new strategy for the synthesis of acyl β-C-glycosides is described. The reactivity of glyconitriles toward organometallic reagents such as organomagnesium or organolithium derivatives was studied, affording acyl β-C-glycosides in moderate to good yields. In this study, glycal formation was efficiently prevented by deprotonating the hydroxyl group in position 2 of the glyconitriles during the process.

Sixteen new isothiazoloisoxazole 1,1-dioxides, one new isothiazolotriazole and one new isothiazolopyrazole have been synthesised by using 1,3-dipolar cycloadditions to isothiazole 1,1-dioxides. One sub-set of these isothiazoloisoxazoles showed low μM activity against a human breast carcinoma cell line, whilst a second sub-set plus the isothiazolotriazole demonstrated an interesting restricted rotation of sterically hindered bridgehead substituents. A thiazete 1,1-dioxide produced from one of the isothiazole 1,1-dioxides underwent conversion into an unknown 1,2,3-oxathiazolin-2-oxide upon treatment with Lewis acids, but was inert towards 1,3-dipoles and cyclopropenones. Six supporting crystal structures are included.

Key structural feature of the new phosphoramidites is a paracyclophane scaffold in which two aryl rings are tethered by both a 1,8-biphenylene unit and a O—P—O bridge.

Planar chiral ferrocenylphosphines give very active gold catalysts for the asymmetric cycloisomerization of 3-hydroxy-1,5-enynes into bicyclo[3.1.0]hexones.

Water-soluble gold(III/I) N-heterocylic carbene complexes behave as efficient catalysts for the hydration of terminal alkynes in neat water. The transformation proceeds in the absence of Bronsted acids or halide scavengers and is suitable for sensitive substrates. Kinetic profiles and DFT studies provide a clear picture of intermediates present during catalysis.

The core structure of (.+-.)-clausenamide (I) and (.+-.)-hyalodendrin (II) are synthesized from a common synthetic precursor based on a phenylalanine derivative in good yield by simple variation of the reaction conditions.

A new approach to enantiopure disubstituted oxaprolinol derivatives through diastereoselective [3+2]-cycloaddition of chiral cyclic ketonitrones to electron-rich and electron-poor dipolarophiles is presented.

Diaryl substituted oxadiazoles are efficiently synthesized from aldehydes and hydrazides via oxidation of the acylhydrazone intermediates (III).

Using the photoreducible CuII precatalyst 2, trifluoromethylation reactions of alkenes are conducted effectively at low copper loading (0.1–0.5 mol%) on exposing the reaction mixture to sunlight/ambient light.

The stereoselective synthesis of a new classes of boronato- or trifluoroborato aminoacids and peptides was described using Wittig and C-H iridium borylation as key reactions. A trifluoroborato-thio...

New thioimidate N-oxides are synthesized by taking advantage of the nucleophilic capability of the thiohydroximate function, anchored on a carbohydrate backbone.

Cycloisomerization of substrates (I) or (V) in the presence of either a gold or a platinum catalyst leads to formation of fused pyridines such as (II) or (VI).

The first examples of catalytic cyclization reactions of the Huisgen zwitterion with α-ketoesters are described.

Review: overview of available multiphotochromic compounds which use a variety of photoactive building blocks, their efficiency in terms of multi-responsiveness and strategies to circumvent the most common limitations; 277 refs.

A series of bicyclic lactams is prepared by a base-mediated reaction of hydroxyl halogenoamides with corresponding Michael acceptors.

Post-functionalization of metal N-heterocyclic carbene complexes (metal NHCs) is described in this focused review. As metal NHCs are nowadays prominent in organometallic chemistry, functionalization methods for these scaffolds are of high importance for numerous applications of these organometallic compounds, ranging from catalysis to medicinal chemistry. Recently, post-functionalization – i.e. chemical modification of a preformed metal complex – has emerged as a set of divergent and modular methods for metal NHC modification. Examples chosen herein highlight that in a near future such methods may increase the number and diversity of biocompatible and bioconjugated metal–NHC complexes.

An overview is presented of the representative members of the wide range of supramolecular host–guest complexes and polymers formed through the association of complementary hydrogen-bonding motifs comprising barbiturates (or structurally related cyanurates in specific cases) and Hamilton-type, bis(amidopyridine) receptor motifs, which offer strong selective binding in non-competitive media. A particular emphasis is placed on photoaddressable systems.

Ilhem Zebiri was born in 1986 in Oran. She is currently in her second year of the Masters program “Chemistry, NaturalSubstances and Medicine” in Reims. She is deeply interested in organic and analytical chemistry (chromatography, NMRspectroscopy), especially directed to the field of natural substances and their extraction methods.Sebastien Balieu was born in 1979 in Rouen, France. He graduated with an M.Sci. degree in Chemistry from RouenUniversity in 2004 under the supervision of Prof. S. Piettre in the field of carbohydrates. He obtained his Ph.D. degreein 2007 from the University of Rennes 1 under the supervision of Dr. B. Boitrel in the field of porphyrins and alpha-therapy. In 2007, he joined the group of Prof. C. Courillon (Paris VII) as a postdoctoral fellow working on ynamidesand radical cyclizations. In 2009, he joined the group of Prof. S. Bouquillon (Reims) as a postdoctoral fellow workingon dendrimers and encapsulation. He is now in the group of Prof. A. Haudrechy (Reims) as a postdoctoral fellow workingon carbohydrates for the synthesis of biologically active molecules.After several jobs in the agri–food and pharmaceutical industries, Arnaud Guilleret has worked for Soliance since 2007as an R&D project manager. He holds an M.Sc. degree in chemistry of natural substances and an herbalist diploma. Hespecializes in phytochemistry and biotechnology.Romain Reynaud is the head of R&D of Soliance. For more than 10 years, he has directly contributed to the discovery,the development, and the launch of more than 30 cosmetic-active ingredients. He holds an M.Sc. degree in formulationchemistry. He worked at ARD (Agro-industrie Recherche et Developpement) for three years and joined Soliance in 2004.Arnaud Haudrechy was born in 1965 in Rouen, France. He obtained his Ph.D. degree in 1990 from the University ofParis VI under the supervision of Prof. P. Sinay in the field of carbohydrates and transition-metal chemistry (Tebbe’sreagent). In 1990, he joined the group of Professor Y. Kishi (Harvard University) as a postdoctoral fellow working onpreferred conformations of C-glycosides. In 1992, he joined the University Paris Sud as a lecturer in organic chemistry,working with Prof. Y. Langlois on low-temperature asymmetric Diels–Alder reactions and a sequential Claisen–Ireland/metathesis concept. He is now full Professor of Organic Chemistry at the University of Reims Champagne-Ardenne, andhis research program is focused on the use of carbohydrates for the synthesis of biologically active molecules.

This account describes the use of phosphines as simple organocatalysts that catalyze the synthesis of complex spirocyclic compounds. Besides our own results, coverage of relevant literature in this field is also provided, including asymmetric variants and synthetic applications. 1 Introduction 2 Cycloaddition Reactions Involving Allenoates or 2-Butynoates 2.1 [3+2] Cycloadditions 2.2 [4+2] Cycloadditions 2.3 [4+1] Cycloadditions 3 [3+2] Cycloadditions with Morita–Baylis–Hillman Adducts 4 Cycloaddition Reactions Using Ynone Derivatives 5 Cycloaddition Reactions Involving Methyl Vinyl Ketone ­ Derivatives 6 Miscellaneous Reactions 7 Conclusions

An enantiopure phosphathiahelicene is prepared and successfully applied as the catalyst for the enantioselective cycloisomerization of N-tethered enynes.

We report herein a versatile cooperative dual catalysis reaction based on a CuI/Pd0 system. Mechanistic investigation shows that every component plays a crucial role in determining the reaction outcome. The reaction is successfully extended to various substrates; such as α,β-unsaturated ketones, malonates and coumarins. The strategy tolerates different substitution patterns and affords good yields for each family of substrates. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A range of valuable 1-indanols and 1-indanamines containing a tertiary C1 atom were synthesized by intramolecular palladium(0)-catalyzed C(sp(3))-H arylation, despite unfavorable steric interactions. The efficiency of the reaction was found to correlate with the degree of substitution at C2, as expected from the Thorpe-Ingold effect. Additionally, the nature of the heteroatomic substituent at C1 had a marked influence on the diastereoselectivity at C1 and C2; indeed, 1-indanols and 1-indanamines were obtained with the opposite relative configuration. Analysis of the X-ray and DFT-optimized structures of the corresponding reactive intermediates provided useful insights into the subtle conformational effects induced by these substituents.

The first example of a high facial selective [3 + 2] cycloaddition employing chiral vinyl ethers as dipolarophile and nitrones as dipoles is presented.

Lipid oligonucleotides (LONs) are emerging as promising supramolecular tools for biomedical and technological applications. In this contribution we highlight recent advances in the area of LONs with an emphasis on their supramolecular properties and applications. In the first section we focus on the design, self-assembly and applications of LONs. In the last section, we describe recent biomedical applications thereof.

This literature overview demonstrates that helically chiral ligands and organocatalysts have been largely neglected so far. However, a few recent studies on helical pyridine, the corresponding ammonium salts and N-oxides have highlighted the significant potential of these compounds as organocatalysts for Michael type additions, aldehyde propargylations, epoxide openings, and others. In addition, helicenes displaying a fused phosphole ring at the end of their polyaromatic structures, have been used as ligands in enantioselective gold promoted cycloisomerization reactions, giving both excellent catalytic activity and high enantiomeric excesses. These recent results are expected to stimulate further research on the catalytic applications of helically chiral auxiliaries in the next few years.

In the presence of the Ru catalyst (RUC), ketonitrones of type (I) are found to react with methacrolein with high regio-, diastereo-, and enantioselectivity.

An efficient one-pot, two-step sequence starting from azide derivatives is described: first, formation of iminophosphoranes (Staudinger reaction) and condensation with carbon disulfide to form nonisolated isothiocyanates; then, condensation with α-amino esters to provide new N-3-substituted 2-thiohydantoins.

The use of phosphahelicenes as chiral ligands in transition-metal catalysis is described for the first time.

A straightforward and efficient synthetic route to a new class of glycosidase inhibitors containing an oxazole-2(3H)-thione moiety has been devised. The approach involves the formation of α-hydroxy ketones, which, after condensation with thiocyanic acid, leads to the formation of the heterocycle. By exploiting the ability of the nitrogen atom of oxazoline-2thione precursors to act as nucleophiles in intramolecular addition, castanospermine analogues could be readily prepared in good overall yields. Glycosidase inhibitory activity com

Modular hemisyntheses of boronato- and trifluoroborato-substituted amino acid derivatives are achieved based on the reaction of Wittig reagent (I) with aldehydes followed by Ir-catalyzed boronation.

A new family of planar chiral phosphoric acids containing a ferrocene unit is prepared with the shown derivative (FPC) giving the best results for the asymmetric transfer hydrogenation of quinolines.

Starting from the at the phosphorus atom (S)-configured molecule (III), the product ratio of the helical stereoisomers (IV) is 33:67 (P:M).

Black crystals of U38O56Cl18(thf)8 (BzO)24·8THF are solvothermally synthesized from a mixture of UCl4, Bz-OH, THF, and a controlled amount of H2O (autoclave, Ar, 130 °C, 36 h, 72% yield).

Triphenylphosphine promoted reactions between 3-arylideneoxindoles and δ-aryl-substituted penta-2,3-dienoates afford an unprecedented access to spirocyclic oxindoles with functionalized six-membered rings. In these new [4 + 2] cyclization processes, the allenoates operate as the four-carbon synthons, thanks to the involvement of the substituted δ-carbons. These reactions give excellent control of the relative stereochemistry of the three stereogenic centers. The stereochemistry of the final product has been ascertained by X-ray diffraction studies.

Screening experiments show that a chiral BINOL-derived Pt-catalyst gives the best results in the cycloisomerizations of 1,5-enynes.

Dendrimers grafted with (S)-α,α-diphenylproline trimethylsilyl ether moieties are presented as organocatalysts.

As a test for the newly presented phosphoric acids their application in an asymmetric transfer hydrogenation of 2-phenylquinoline with Hantzsch-type esters is reported.

The large diversity and complexity of glycan structures together with their crucial role in many biological or pathological processes require the development of new high-throughput techniques for analyses. Lectins are classically used for characterising, imaging or targeting glycoconjugates and, when printed on microarrays, they are very useful tools for profiling glycomes. Development of recombinant lectins gives access to reliable and reproducible material, while engineering of new binding sites on existing scaffolds allows tuning of specificity. From the accumulated knowledge on protein–carbohydrate interactions, it is now possible to use nucleotide and peptide (bio)synthesis for producing new carbohydrate-binding molecules. Such a biomimetic approach can also be addressed by boron chemistry and supra-molecular chemistry for the design of fully artificial glycosensors.

The phosphine-promoted [3 + 2] cyclizations between γ-substituted allenoates and arylideneoxindoles have been applied to the stereoselective synthesis of spiro(cyclopentene)oxindoles with trisubstituted cyclopentene units. It has been demonstrated that PPh(3) operates a very efficient control of the relative stereochemistry of the three stereogenic centers of the final spiranic products. Focused experiments have been carried out then so as to access carbocyclic analogues of an important series of anticancer agents inhibiting MDM2-p53 interactions.