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11.
12.
The discovery of synthetic pyrethroids with increased insecticidal activity and low mammalian toxicity led to abundance of new synthetic results in the chemistry of pyrethroids1 . Many of these methods adopted on an industrial scale make use of sigmatropic rearrangement, radical addition and nucleophilic ring closer with carbanions. Herein we report a simple and stereospecific route for the synthesis of ethyl trans-chrysanthernate (1) by utilizing carbonyl stabilized sulphuranes. Although the use of Sulphurane was demonstrated at a much earlier stage for the synthesis of methyl trans-chrysanthe-mate2, the present approach makes use of simple reagents and offers some operational advantages. 相似文献
13.
Nagaraju Kerru Lalitha Gummidi Surya Narayana Maddila Sandeep V.H.S. Bhaskaruni Sreekantha B. Jonnalagadda 《应用有机金属化学》2020,34(5):e5590
The bismuth loaded on fluorapatite (Bi2O3/FAp) proved to be an excellent catalyst for the synthesis of novel dihydro-[1,2,4]triazolo[1,5-a]pyrimidine derivatives via a three-component reaction involving the mixture of 1H-1,2,4-triazol-5-amine, ethyl cyanoacetate or ethyl acetoacetate, and different benzaldehydes in ethanol at room temperature. The catalyst material was characterized by X-ray diffraction, Brunauer–Emmett–Teller surface area analysis, Fourier-transform infrared, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy techniques. The efficacy of Bi2O3/FAp as a heterogeneous catalyst was evaluated with the loading of different wt% of bismuth on FAp. The 2.5% bismuth on FAp performed extremely well as a catalyst with a high yield of products (92%–96%) in a short reaction time (25–35 min). The catalyst was recovered by simple filtration. It showed undiminished activity up to five runs. Simple work-up, room temperature reaction, short reaction time, high yields, no column chromatography, and good reusability of catalyst are the merits of the proposed protocol. In addition, this process offers 100% carbon efficiency and 98% atom economy with noteworthy fiscal and environmental benefits. 相似文献
14.
Bromination of alkenes with sodium bromide in the presence sodium perborate provides a simple, high yield route to dibromoalkanes. 相似文献
15.
16.
K. K. Vijaya Raj B. Narayana 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1971-1981
A smooth one-step synthesis of 2-(2-bromo-5-methoxyphenyl)-5-(3-arylidene)-1,3-thiazolo[3,2-b]-1,2,4-triazol-6-(5H)-ones (4a–n) is described. The newly prepared compounds are characterized by analytical and IR, 1 H NMR, 13 C NMR, and FABMS spectral analysis. A few compounds are screened for anticonvulsant activity. Compounds 4i and 4n exhibit promising anticonvulsant activity and are recommended for further studies. 相似文献
17.
A simple method for the synthesis of amines by the reduction of imines, anils and enamines, including some chiral substrates, with the MCl2/NaBH4/CH3OH reagent (M = Co, Ni) in 64–82% yields is described. 相似文献
18.
Konkala Karnakar Katla Ramesh Sabbavarapu Narayana Murthy Yadavalli Venkata Durga Nageswar 《Helvetica chimica acta》2013,96(12):2276-2281
The first example of the stereoselective synthesis of (Z)‐ and (E)‐allyl aryl sulfides and selenides from Baylis? Hillman acetates under neutral conditions in H2O by supramolecular catalysis involving β‐cyclodextrin is reported. β‐Cyclodextrin can be recovered and reused. The reaction is very efficient in providing allyl aryl sulfides and selenides in good‐to‐excellent yields with clean reaction profiles under mild reaction conditions. 相似文献
19.
A. Babulreddy R. V. Hymavathi Md. Manzoor Hussain G. Narayana Swamy 《Journal of heterocyclic chemistry》2013,50(3):727-733
A new class of methyleneamine‐linked bis‐heterocycles that exhibit antimicrobial activity was synthesized. Bromination of 1 followed by condensation with thiourea gave 3 . The reaction of 3 with propargyl bromide in dry toluene under inert atmosphere led to the formation of 4 . Its subsequent reaction with different nitrile oxides using CuSO4.5H2O–sodiumascorbate system in a 2:1 mixture of water and tert‐butyl alcohol yielded the title compounds 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j , 6k , 6l in good yields. The identities of these compounds were confirmed following elemental analysis, IR, 1H, 13C NMR, and mass spectral studies. All the title compounds exhibited pronounced in vitro antibacterial and antifungal activities. 相似文献
20.
Reaction of 2-pyridylmagnesium chlorides with N,N-dialkyl arylamides afford exclusively 2-(aroyl) pyridines in high yields and purity without the formation of any tertiary alcohol. This method employs easily available raw materials and avoids the use of hazardous lithium reagents and cryogenic conditions. Further, preferential reactivity of this Grignard reagent with N,N-dialkyl arylamides over its carbonitrile counterparts offers a variety of 2-(aroyl) pyridines including the ones containing carbonitrile groups on the aryl ring. 相似文献