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Three compounds with a bent rod-like aromatic core and with three alkoxy chains at each end were synthesised by click reaction. The compounds form a columnar liquid crystal phase with non-centrosymmetric trigonal p31m symmetry, the columns having a 3-arm star-like cross-section. [ABSTRACT FROM AUTHOR]

Rhodium complexes coordinated by Chenphos are very effective catalysts for the enantioselective hydrogenation of α-aryloxy- and α-alkoxy-substituted α,β-unsaturated carboxylic acids under mild conditions in CF3CH2OH. The catalytic system could be successfully employed in building the core structure of a new FDA approved drug LCZ 696. [ABSTRACT FROM AUTHOR]

A single-handed helical polymer ligand PQXphos afforded axially chiral biaryl esters with high enantioselectivities in asymmetric Suzuki–Miyaura cross-coupling. The use of naphthyl bromide bearing a 2,4-dimethyl-3-pentyl ester resulted in both high yields and high enantioselectivities. Either enantiomer could be synthesized selectively by using a single PQXphos through a solvent-dependent switch of the helical chirality. [ABSTRACT FROM AUTHOR]

A highly efficient recognition phenomenon was observed between alkoxylated arylene--ethynylene macrocycles bearing identical side chains but different core size, which is based on van der Waals interactions between alkoxy chains. The ratio of both molecules and the environment of each molecule have been statistically analyzed to quantify the recognition efficiency. [ABSTRACT FROM AUTHOR]

An efficient iron(II)-catalyzed alkoxycarbonylation reaction between N-vinylacetamides and carbazates is reported. The corresponding useful highly substituted (b-acylamino)acrylates could be obtained in reasonable to good yields and stereoselectivity under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Linear trimetallic CoIII/CoII/CoIII cobalt complexes with bridging acyl-alkoxy ligands are electrocatalysts for the reduction of tosic acid in acetonitrile. The -OCMe2CH2COMe complex appears to operate homogeneously, and at a modest onset overpotential of 175 mV. A turnover frequency of ca. 80 s-1 was observed at an overpotential of 300 mV. [ABSTRACT FROM AUTHOR]

Selective α-amination and α-acylation of esters and amides have been developed, employing O-acylhydroxylamines as a dually reactive aminating and acylating reagent. Treatment of zinc enolates with O-acylhydroxylamines provides solely 1,3-dicarbonyl compounds under mild conditions. Introduction of a copper catalyst into the system shifts the reactivity entirely, yielding α-amination products exclusively. [ABSTRACT FROM AUTHOR]

A nickel-catalyzed α-arylation of esters and amides with phenol derivatives has been accomplished. In the presence of our unique nickel catalyst, prepared in situ from Ni(cod)2, 3,4-bis(dicyclohexyl-phosphino) thiophene (dcypt), and K3PO4, various esters and amides undergo α-arylation with O-arylpivalates or O-arylcarbamates to afford the corresponding coupling products. The thus obtained α-aryl esters and amides are useful precursors of privileged motifs such as α-arylcarboxylic acids and β-arylamines. [ABSTRACT FROM AUTHOR]

Through the precise molecular design for alkoxy dehydro[12]annulene derivatives harnessed by a diacetylene unit in each alkyl chain, porous two-dimensional networks with giant pores were formed at the liquid/graphite interface. [ABSTRACT FROM AUTHOR]

An unprecedented three-component oxysulfenylation reaction of alkenes with sulfonyl hydrazides and alcohols has been developed in the presence of 20 mol% iodine to give a range of structurally diverse β-alkoxy sulfides in good to excellent yields. [ABSTRACT FROM AUTHOR]

The coupling of acetals with various alkynes was achieved using only 1 mol% of inexpensive and mild Lewis acid ZnCl2, which furnished propargyl ethers. The coupling was catalyzed by Zn(OMe)Cl, which was generated in situ to form an alkynylzinc species. This protocol was allowed to expand to a one-pot subsequent reaction with allylchlorosilane to obtain a 1,4-enyne product. [ABSTRACT FROM AUTHOR]

Intramolecular cyclization of nitrogen-tethered alkynyl esters catalyzed by phosphazene organosuperbases P2-tBu and P4-tBu was investigated. Both acyclic and cyclic substrates underwent 5-exo-dig and 5-endo-dig cyclization. This reaction is a rare example of the intramolecular addition of enolates of simple esters to alkynes. [ABSTRACT FROM AUTHOR]

IBX facilitated the reaction of β-enamino esters with allylic alcohols affording a direct, one-pot and metal free synthesis of functionalized pyridines including 2-substituted nicotinic acids, densely substituted pyridines and precursors of azafluorenones. The methodology also afforded the racemic pyridine core of cyclothiazomycin. [ABSTRACT FROM AUTHOR]

The halo-assisted intramolecular addition of silyl enol ethers with in situ activated lactams yielded (hydroxylated) 1-halo-8-azabicyclo[3,2,1]octane and 1-halo-9-azabicyclo[3,3,1]nonane ring systems, which provided an easy enantioselective access to 6β-silyloxytropane-3-one, 3α,6β-dihydroxytropane, and pervilleine B. The absolute configuration of the natural (−)-pervilleine B was determined to be 1R,3R,5S,6R. [ABSTRACT FROM AUTHOR]

A range of terminal alkenes smoothly underwent palladium-catalyzed oxidative alkoxycarbonylation with carbazates under an oxygen atmosphere to afford structurally diverse α,β-unsaturated esters in moderate to good yields with excellent regioselectivity and E selectivity. [ABSTRACT FROM AUTHOR]

Changing the linking positions of alkoxy chains can significantly alter the aggregation-induced emission and piezofluorochromic activities of 9,10-bis(alkoxystyryl)anthracenes. [ABSTRACT FROM AUTHOR]

A highly enantioselective trapping of protic phosphoramidate ammonium ylides with α-imino esters is reported. The intriguing Rh2(OAc)4 and chiral Brønsted acid co-catalyzed three-component Mannich-type reaction of a diazo compound, a phosphoramidate, and an α-imino ester provides a rapid and efficient access to 2,3-diaminosuccinic acid derivatives with a high level control of diastereo- and enantioselectivity. [ABSTRACT FROM AUTHOR]

The Au(i)-catalyzed intermolecular hydroalkoxylation of alkynes with allylic alcohols to provide allyl vinyl ethers that subsequently undergo Claisen rearrangement is reported. This new cascade reaction strategy facilitates the direct formation of γ,δ-unsaturated ketones from simple starting materials in a single step. [ABSTRACT FROM AUTHOR]

Enantioselective Pd(ii)-catalyzed construction of [3.3.1]-bicyclic ketals from 2-hydroxyphenylboronic acid 1 and enone 3 is reported, yielding enantioenriched [3.3.1]-bicyclic ketals in up to 97% yields and 98% ee. [ABSTRACT FROM AUTHOR]

An efficient metal free protocol has been developed for the synthesis of benzylic esters via a cross dehydrogenative coupling (CDC) involving alkylbenzene(s) as a self- or as a cross-coupling partner(s) via the intermediacy of Ar–COOH and the benzylic carbocation obtained from the other half of the alkylbenzene; both symmetrical as well as unsymmetrical esters can be prepared using Bu4NI and TBHP. [ABSTRACT FROM AUTHOR]

The reaction of acetylene ethers with difluorocarbene (CF2), generated from the Ruppert–Prakash reagent, unexpectedly gave rise to co-produced fluorinated bicyclic [2.1.1]-hex-2-ene and cyclohepta-1,4-diene ring products. [ABSTRACT FROM AUTHOR]

A new metal-free protocol is described for the synthesis of terminal acetals by tandem oxidative rearrangement of olefins using oxone as an oxidant in the presence of iodine. Moreover, a one-pot procedure for the preparation of glycol mono esters from olefins is also presented for the first time using the same reagent system. [ABSTRACT FROM AUTHOR]

The article focuses on a study regarding the effect on the viscosity and melting point of ionic liquids (ILs) due to introduction of ether oxygen atom into an ILs containing polyfluoroalkoxyborate anion. It discusses the preparation, physical, thermal and electrochemical properties of ILs containing same anion. It further includes that ether oxygen increases the ionicity of ILs containing aliphatic quaternary ammonium cations.