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21.
Dehydration of oximes and amides to nitriles was carried out using the AlCl(3) x 6H(2)O/KI/H(2)O/CH(3)CN system. It produced isoquinoline derivatives 8a-c (Bischler Naperialski reaction) when reacted with amides 7a-c in hydrated media. Also, the keto oximes produced anilides (Beckmann rearrangement) with the system under the same reaction conditions. 相似文献
22.
Kalita Amlan Jyoti Sahu Prem Prakash Borah Ritam Raj Rohman Shahnaz Sultana Kashyap Chayanika Ullah Sabnam Swabaka Baruah Indrani Mazumder Lakhya Jyoti Konwar Dimpul Guha Ankur Kanti 《Structural chemistry》2021,32(6):2313-2318
Structural Chemistry - Sandwich complexes find their interests among the chemists after the breakthrough discovery of ferrocene. Since then, a number of sandwich and half-sandwich complexes were... 相似文献
23.
A study of Pentacene OTFTs using La2O3 as gate insulator is presented. The device characteristics were studied and analyzed. The OTFTs exhibit p-type conductivity with field effect mobility 6.5 × 10−8 m2/V.s, ON/OFF ratio 1.4 × 102, sub-threshold swing 2 mV/decade and hole concentration 4.5 × 1017 cm−3. The SEM and XRD analysis on the semiconductor film are also reported. 相似文献
24.
Two new cassane butenolides, caesalpinolide A (1) and B (2), epimeric at the hemiketal position were isolated from the marine creeper Caesalpinia bonduc. The structures were elucidated by the analysis of spectroscopic data and relative stereochemistry was assigned on the basis of ROESY correlations. Compounds 1 and 2 were found to inhibit MCF-7 breast cancer cell lines with IC50 values of (μM) 12.8 and 6.1, respectively, along with the inhibition of endometrial and cervical cancer cell lines. 相似文献
25.
Nanotechnology holds the prospective for pervasive and avant-garde changes to improve performance of materials. Mesua ferrea L. seed oil based highly thermostable and biodegradable polyester/clay nanocomposites have been prepared at different dose levels of nanoclay. The highly branched polyester resin was synthesized by condensation of 2,2-bis(hydroxymethyl) propionic acid with M. ferrea L. seed oil based carboxyl terminated pre-polymer. FTIR, rheometric, XRD, SEM and TEM studies unmasked well-dispersed partially exfoliated nanocomposites with good interfacial interaction. The results showed 2.6 and 6 times increase of tensile strength and elongation at break respectively, and about 150 °C increase of thermostability by the influence of nanoclay loading (1-5 weight %) compared to the pristine polymer. Two strains of Pseudomonas aeruginosa (PN8A1 and vs1) and one Bacillus subtilis strain (MTCC73) were used to study microbial degradation of pristine polymer and nanocomposite systems, with the revelation of enhanced degradation with increasing nanoclay loading. 相似文献
26.
The stereoselective synthesis of 2-isoxazolidine through 1,3-dipolar cycloaddition reaction of nitrile oxide, which is in situ generation from aldoxime in the presence of N-bromosuccinamide and solid-supported reagent KF/Al2O3 at room temperature, is reported. KF/Al2O3 is sufficiently basic such that it can replace organic bases such as Et3N used in typical procedures and it catalyses the reaction to enhance the rate of the reaction. 相似文献
27.
AlCl3 · 6H2O/KI/CH3CN/H2O, an efficient and versatile system, cleaves the C–O bonds of esters, acetals, ethers, and oxathiolanes to the corresponding acids, alcohols, and carbonyl compounds chemoselectively at 80 °C in hydrated media with good yields. This system also converts the alcohols (primary/secondary) to halides and oxidizes the alcohols (primary/secondary) to the corresponding carbonyl compounds in the presence of DMSO. 相似文献
28.
An emission band system in the region 5700–6700 Å from Dergaon stoney iron meteorite which fell at Dergaon, India on March 2, 16.40 local time (2001) was excited with the help of a continuous 500 mW Ar+ laser. The band system is attributed to silicate (olivine), a major component of the meteorite. 相似文献
29.
Das Pankaj Konwar Dilip Sengupta Pinaki Dutta Dipak K 《Transition Metal Chemistry》2000,25(4):426-429
Rhodium(I) carbonyl complexes [Rh(CO)2ClL] where L = Ph3PO, Ph3PS and Ph3PSe, were synthesized and characterized by elemental analysis, i.r. and by 1H-, 13C- and 31P-n.m.r. spectroscopy. The vBD;(CO) band frequencies in the complexes follow the order: Ph3PO > Ph3PS > Ph3PSe, in keeping with the hard/soft nature of the interactions. The complexes undergo oxidative additions with electrophiles
such as MeI, PhCH2Cl and I2 to give, e.g. [Rh(CO)(COMe)ClIL] which react with PPh3 to give trans-[Rh(CO)Cl(PPh3)2]. The catalytic activity of the [Rh(CO)2ClL] complexes in carbonylation of MeOH is higher than that of the well-known [Rh(CO)2I2]− species.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
30.
The d + d, t + p and h + n relative wavefunctions and their asymptotic normalizations are considered in the framework of the generator coordinate method
(GCM) and compared with ATMS (amalgamation of two-body correlation into multiple scattering processes) method which used the
realistic Reid soft core interaction. The asymptotic normalization of relative wavefunctions provide various coupling constants,
the cluster probability amplitude (the so-called Z
1/2-factor) and matter RMS radii. These wavefunctions are also used to obtain 4He − d − d, 4He − t − p and 4He − h − n vertex functions in the virtual decay of 4He. The extrapolation of vertex functions for negative values of q
2 upto the corresponding poles provide the vertex constants which are comparable with other estimates. It is noticed that in
GCM the coupling constants C
2 for 4He − d − d vertex is less than 2 as has been obtained in the forward dispersion relation technique. 相似文献