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This study examines the quality and structural integrity of bituminous mixes in road construction. An innovative and non-destructive evaluation (NDE) approach is employed, specifically utilizing a log-periodic feedlines (LPFs) based ring filter. This study investigates the correlation between the existence of voids, attenuation, and group delay in various bituminous mix samples through the utilization of microwave imaging. The results show that for non-porous samples with 3.24% average porosity and 16.978 kN average load, the slope change for attenuation ( $\alpha $ ) is 56.9%, while group delay ( $\tau _{g}$ ) is 43.94%. Porosity changes significantly, with a 50% shift in slope $\alpha $ and a 58% change in $\tau _{g}$ , respectively, demonstrating that the areas with higher group delay and attenuation suggest the existence of voids. The relationships between group delay and attenuation with load and porosity are indicated by $R^{2}$ values of 0.82 and 0.79 for load and 0.85 and 0.79 for porosity, respectively (for porous samples) and 0.83 and 0.8 for load and 0.82 and 0.86 for porosity, respectively (for non-porous samples). This provides valuable knowledge regarding potential deficiencies in road construction materials. The research presented in this study contributes to the importance of electromagnetic (EM) wave-based testing methods by establishing a correlation between these variations and the quality of bituminous mixes.

Herein we report, a single-pot multistep conversion of inactivated carboxylic acids to various N-containing compounds using a common synthetic methodology. The developed methodology rendered the use of carboxylic acids as a direct surrogate of primary amines, for the synthesis of primary ureas, secondary/tertiary ureas, O/S-carbamates, benzoyl ureas, amides, and N-formyls, exploiting the Curtius reaction. This approach has a potential to provide a diversified library of N-containing compounds, starting from a single carboxylic acid, based on the selection of the nucleophile.

The formability characteristics of interstitial free high strength (IFHS) steels are significantly governed by processing parameters of steel at consecutive processing stages, chiefly hot rolling of slabs followed by cold reduction of hot rolled coils and finally annealing treatment of cold reduced coils. The present work focuses on investigating the steel processing parameters for a chosen set of processing parameters which in turn influence the final formability of the steel. The underlying objective is to study the effect of steel processing parameters, which in turn favorably control texture, microstructure, precipitate morphology and its distribution at each step to impart desired properties in the steel sheet in the end. In the current work, an IFHS steel chemistry is chosen with an objective to evaluate the contribution of texture, microstructure and precipitates generated at each processing step to the formability in relation with the chosen processing parameters.

The manuscript describes a synthetic route for the formation of 5‐(methylisoindole‐1,3‐dione) pyrimidinones by [4+2] cycloaddition reactions of functionalized 1,3‐diazabuta‐1,3‐dienes with 2‐(3‐Oxo‐allyl)‐isoindole‐1,3‐dione generated in situfrom phthaloylalanine and tosyl chloride using triethylamine as a base. The functionalized 5‐(methylisoindole‐1,3‐dione) pyrimidinones were further explored in the deprotection of amines to afford a variety of 5‐methylamino pyrimidinones. The synthesis of such functionalized pyrimidinones is significant as they have a wide range of pharmacological profiles and are valuable as organic synthons. Mechanistic insights are also proposed for the given synthetic methodology. The manuscript describes the formationof 5‐(methylisoindole‐1,3‐dione) pyrimidinones by [4+2] cycloaddition reactions of functionalized 1,3‐diazabuta‐1,3‐dienes with 2‐(3‐Oxo‐allyl)‐isoindole‐1,3‐dione generated in situfrom phthaloylalanine and tosyl chloride using triethylamine as a base. The functionalized 5‐(methylisoindole‐1,3‐dione) pyrimidinones were further explored in amine deprotection to afford a variety of 5‐methylamino pyrimidinones. The synthesis of such functionalized pyrimidinones is significant as they have a wide range of pharmacological profiles and are valuable as organic synthons.

The regioselective nitroso Diels-Alder (NDA) reactions of trans 3-butadienyl-2-azetidinones with nitrosoarenes leading to the synthesis of novel and diastereomerically pure 3-(3,6-dihydro-2H-1, 2-oxazin-6-yl) azetidin-2-one derivatives and cis 3-butadienyl-2-azetidinones resulting in a diastereoselective mixture of regioisomers are investigated. The observed regioselective behavior is supported by computational model, Ab initio [HF/6-31G (d)] and density functional theory [B3LYP/6-31G (d)] calculations. Additionally, the effect of solvation (in dichloromethane) in these reactions was also investigated in order to mimic the experimental solvent conditions.

The convenient and facile synthesis of tetra/octahydroisoquinolones has been developed and validated by using inter/intramolecular amidolysis of racemic N‐aryl‐β‐lactams followed by intramolecular iodocyclization protocols. Thesingle‐pot synthetic version of the desired conversion was successfully developed. The single‐pot synthesis of tetrahydro‐4H‐isoquinoline‐1,3‐diones invariably resulted in aromatic electrophilic iodination rather than the desired iodocyclization in cases where N‐phenyl‐2‐azetidinones were employed as the synthetic precursors.

Now with nickel:[3C+2C+2C] cycloadditions involving non‐activated alkylidenecyclopropanes provide a practical entry to a variety of interesting 6,7‐fused bicyclic systems (see scheme; cod=1,5‐cyclooctadiene). DFT calculations, combined with experimental data, suggest that the catalytic cycle involves the initial formation of 1‐alkylidenenickelacyclobutane intermediates, such as 1.

Jetzt auch mit Nickel: Nickelkatalysierte [3C+2C+2C]‐Cycloadditionen unter Beteiligung nichtaktivierter Alkylidencyclopropane öffnen einen Zugang zu vielfältigen kondensierten 6,7‐Bicyclen (siehe Schema; cod=1,5‐Cyclooctadien). Dichtefunktionalrechnungen und experimentelle Daten sprechen für einen Katalysezyklus, der mit der Bildung von 1‐Alkylidennickelacyclobutan‐Intermediaten wie 1beginnt.

AbstractSeveral thieno [3,2-d]pyrimidin-4-ones (4a-i)were conveniently prepared by the thio-claisen rearrangement of 5-prop-2-ynylsulfanyl pyrimidin-4-ones derivatives. The constitution of the products was supported by IR, PMR and mass spectral study. The compounds synthesized were tested in vitro against gram positive microorganisms, Bacillus subtilis, Bacillus cereus, Staphlococus aureus, Enterococcus faecalisand gram negative microorganism Eseherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Klabsiella pneumoniaeand Shigella sonnei.Standard drugs were also tested under identical conditions for comparing the results.

Diastereoselective and π-facially selective Lewis acid-catalysed intermolecular Diels–Alder reactions of 3-butadienylazetidin-2-ones with a variety of symmetrical dienophiles (maleic anhydride, N-phenylmaleimide, N-p-tolylmaleimide, benzoquinone and naphthoquinone) resulting in the synthesis of diastereomerically pure 1,3,4-trisubstituted 2-azetidinones are reported. The effects of different Lewis acids on the yields of the selectively formed diastereoisomers under different reaction conditions are also examined. Preferential chelation between the Lewis acid complexes of the different dienophiles and the carbonyl oxygens in the dienylazetidin-2-ones has been invoked to explain the observed π-facial selectivity. The Lewis acid complexes of the dienophiles have been shown to approach preferentially from the si-faces of the dienes, resulting in the formation of π-facially selective “endo” adducts. The structures of these “endo” adducts have even been supported by X-ray diffraction studies. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

β‐Lactams (I) bearing an ester group at the 3‐position are transformed in a single step into the desired octahydroquinolones (II) by treatment with MeONa in refluxing xylene.

Contrary to previous palladium‐ or rhodium‐catalyzed cycloadditions of alkynylidenecyclopropanes, which result in the formation of cycloadducts arising from the distal opening of the cyclopropane, the current method gives complementary 6,7‐fused bicyclic systems resulting from cleavage of the proximal bond of the ring.

A two‐step sequence involving cleavage of β‐lactams with sodium methoxide and subsequent cyclization of the resulting amino esters affords novel diastereomerically pure title compounds (IV).

The three‐step sequence involves regioselective nitro‐Diels—Alder cycloaddition of lactams (I) with nitrosobenzene, cleavage of the lactam ring and intramolecular iodocyclization.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.