Acyclic Anhydrides Research Articles

Double-Decker-Type Dipalladium Catalysts for Copolymerization of Ethylene with Acrylic Anhydride

Dipalladium complex with a macrocyclic ligand having two diimine sites catalyzes copolymerization of ethylene with acrylic anhydride to afford the copolymer containing the repeating unit from acrylic anhydride. The obtained copolymer contains the cyclic and acyclic anhydride groups in high content (up to 5.7 mol %) in the main chain. It is contrasted with that the monopalladium complex with the diimine ligand catalyzes the reaction to yield the copolymer having the polar group at the end of branches with lower content (0.8 mol %). Decreased ethylene pressure of the reaction using the dipalladium catalyst results in increase in the polar comonomer unit content. Methanolysis of the copolymer takes place smoothly to give the polymer with both carboxylic acid and ester groups in the polymer chain.

Manifestation of Felkin–Anh Control in Enantioselective Acyl Transfer Catalysis: Kinetic Resolution of Carboxylic Acids

Under control: The classical polar Felkin–Anh model has been applied for the first time to the analysis of diastereoselectivity in acylation reactions (see scheme). Computational studies demonstrate that stereoelectronic effects control the enantioselectivity in asymmetric catalytic alcoholysis of acyclic anhydrides.

Efficient synthesis of symmetrical and unsymmetrical acyclic imides catalyzed by reusable 12-tungstophosphoric acid under thermal conditions and microwave irradiation

An efficient and environmentally friendly procedure has been developed for the synthesis of symmetrical and unsymmetrical acyclic imides by the reaction of nitriles with acyclic anhydrides in the presence of catalytic amounts of 12-tungstophosphoric acid (H3PW12O40) under thermal conditions and microwave irradiation. It was found that microwave improves the yields and significantly reduces the reaction times. Furthermore, the catalyst could be recovered and reused several times without decrease in its activity.

Piperonylic anhydride: Isolation and conformational analysis by X-ray crystallography and density functional theory calculations

The title compound ( 1), a symmetrically substituted acyclic anhydride, is shown to crystallise in the monoclinic space group P2 1/ n with a = 4.7032(1) Å, b = 17.8748(6) Å, c = 15.6869(5) Å, β = 98.3980(17)° and V = 1304.64(7) Å 3. There are four molecules in the unit cell. Bond lengths and angles of 1 are comparable to the limited number of benzoic anhydride crystal structures that have been previously disclosed. Compound 1 adapts a syn-conformation in the solid-state with a pseudo-torsion angle for the O C⋯C O groupings of approximately 25.1°. This structure is compared to other benzoic anhydride (BA) materials that have been structurally elucidated either via single crystal X-ray diffraction methods and/or examined from a theoretical perspective. Calculations at the DFT level (B3LYP 6-311G **) for a theoretical gas phase molecule of 1 reveals a similar overall global structure to that observed in the solid-state; these results suggest that crystal packing effects are negligible with respect to the observed ground state syn-conformation in the solid phase. Compound 1 also represents the first structurally characterised di-substituted benzoic anhydride.

O-Nitrobenzoic acid anhydride

The title compound, C14H8N2O7, is a symmetrically substituted acyclic anhydride. The nitro groups are twisted with respect to the benzene rings; these are almost coplanar, with a dihedral angle of 9.07 (9)°.

Chemoselective Acylation of Amines in Aqueous Media.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Mild and eco-friendly chemoselective acylation of amines in aqueous medium

Amines in the form of amine hydrochlorides are efficiently acylated with anhydrides in an aqueous medium on addition of NaHCO3. Both cyclic and acyclic anhydrides react with equal ease with an amine and amines of various stereo-electronic factors react with the same rates with an anhydride. No chromatographic separation is needed for isolation of the acylated product. Reactions in aqueous medium, innocuous by-products and chemoselective acylation of amines in the presence of phenols and thiols have been achieved with high selectivity.

Chemoselective Acylation of Amines in Aqueous Media

AbstractAmines are efficiently acylated by both cyclic and acyclic anhydrides by dissolving them in an aqueous medium with the help of a surfactant, sodium dodecyl sulfate (SDS). Cyclic and acyclic anhydrides react with equal ease with an amine, and amines with various stereo‐electronic factors react at the same rates with an anhydride. Chemoselective acylation of amines in the presence of phenols and thiols and of thiols in the presence of phenols has been achieved. No acidic or basic reagents are used during the reaction. No chromatographic separation is required for isolation of the acylated products. Reactions in a neutral aqueous medium, easy isolation of products, and innocuous by‐products make the present method a green chemical process. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Preparation of Acyl(carboxylato)bis(tertiary phosphine)palladium(II) Complexes by C–O Bond Cleavage of Carboxylic Anhydrides on Interaction with Palladium(0) Complexes. Catalytic Hydrogenation of Carboxylic Anhydrides to Aldehydes by Palladium Complexes

Abstract Acyclic anhydrides oxidatively added to [Pd(styrene)(PMeR2)2] (R = Me, 2a; Ph, 2b) under mild conditions with C–O bond cleavage to give the corresponding trans-acyl(carboxylato)palladium complexes 3a—3h. Cyclic acid anhydrides also added to 2a to yield trans-acyl(carboxylato)palladium complexes 4a—4c, while reaction of 2a with phthalic anhydride afforded the palladalactone 4d generated via oxidative addition followed by decarbonylation. The acetyl(acetato)palladium complex 3a reacted with dihydrogen or formic acid to give acetaldehyde and acetic acid. Catalytic hydrogenation of acyclic anhydrides by a palladium complex was achieved to form the corresponding aldehydes and carboxylic acids.

Dimethyl 2,2,6,6-Tetramethyl-3,5-dioxo-4-oxaheptanedioate

The title compound, C 12 H 18 O 7 , crystallizes with the anhydride moiety non-planar and in the trans, trans conformation. The stability of this compound suggests that quatemary C atoms attached to carbonyl C atoms have a stabilizing influence on acyclic anhydride compounds.

Thermo-oxidative behaviour of water-borne ink binders in the presence of monovalent metal ion

As a part of continuing studies on the change in solubility characteristics of water-borne flexo ink binders, the thermal behaviour of unneutralized and partially or completely neutralized acrylic copolymer and styrene-maleic anhydride copolymer has been examined relative to a water-based ink binder having no carboxylic acid or anhydride group. Films of ink binder and the inks prepared with these binders were aged at 105 °C before or after adding sodium hydroxide. Solubility behaviour as determined by a swelling study revealed that water solubility of acrylic binder decreased significantly after acid group neutralization and ageing. Styrene-maleic anhydride copolymer also showed similar behaviour but the effect on solubility was less significant. Thermogravimetric and FTIR analyses results suggested a crosslinking reaction by acyclic anhydride formation due to alkali catalysed heating of acrylic and maleic binders. By contrast, the presence of univalent metal ion in a sulfopolyester-based flexo ink binder did not show any crosslinking effect and the water solubility of this binder remained practically unchanged.

Chemical behaviour of N‐(2‐hydroxybenzyl)anthranilic acids in the presence of acyclic anhydrides

AbstractThe synthesis of 11‐acyl‐11,12‐dihydrodibenz[bf][1,5]oxazocin‐6‐ones 9‐13 is reported by reaction of N‐(2‐hydroxybenzyl)anthranilic acids 1 with acetic, isobutyric, 2‐ethylbutyric anhydrides. The structures of the obtained 6,8,6 products are proved with the use of ir, mass spectrometry, 1H and 13C nmr spectra, homo‐and heteronuclear two‐dimensional nmr experiments. The formation of 9‐13 is discussed in relation to the obtainment of 12H‐quino[2,1‐b][1,3]benzoxazin‐5‐ones 2‐8 and 6a,12‐dihydro[3,1]benzoxazino[2,1‐b][1,3]‐benzoxazin‐5‐ones 14‐19 from the same starting products 1 with suitable anhydrides under controlled reaction conditions.

Acylation of Phenol by Cyclic and Acyclic Anhydrides in Anhydrous Acetic Acid

AbstractAcylation of phenol with succinic, glutaric, trans-1,2-cyclohexanedicarboxylic, maleic, phthalic, and cis-1,2-cyclohexanedicarboxylic anhydrides in anhydrous acetic acid generally resulted in phenyl acetate as the major product. The formation of phenyl acetate as the major reaction product could be rationalized as being due to the reactivity of the cyclic anhydrides with acetic acid to form acetic anhydride as well as the greater reactivity of phenol with formed acetic anhydride than with the cyclic anhydride.

ChemInform Abstract: THE REACTION OF ACID ANHYDRIDES, DIBASIC ACID DIESTERS, AND DIBASIC ACIDS WITH VINYLMAGNESIUM CHLORIDE

AbstractDie Reaktion von Säureanhydriden wie (I), Dicarbonsäuredimethylestern wie (VII) und Dicarbonsäuren mit Vinyl‐Mg‐chlorid (II) werden untersucht und am Beispiel von Isobuttersäureanhydrid (Ia) und dem Adipinsäureester (VIIa) beschrieben.