Iron-catalyzed synthesis of pyridines from α,β-unsaturated ketoxime acetates and N-acetyl enamides

Synlett ◽  
2021 ◽  
Author(s):  
Gaochen Xu ◽  
Huan Yan ◽  
Sai Zhang ◽  
Qinghuan Wu ◽  
Jindian Duan ◽  
...  

A new method of FeCl2-catalyzed [4 + 2] annulation of α,β-unsaturated ketoxime acetates with N-acetyl enamides in batch and flow is reported. The current strategy features low-cost catalytic system, use of electron-rich olefins, operational simplicity and broad substrate scope, thus providing a facile and efficient access to substituted pyridines in moderate to good yields.

2019 ◽  
Author(s):  
John Montgomery ◽  
Alexander W. Rand

A new method to access alpha-arylated benzamides has been enabled by metallaphotoredox catalysis. This system allows for non-directed C–H functionalization of N-alkyl benzamides using a dual nickel/iridium catalytic system to form tertiary stereocenters in good enantiomeric excess and moderate yields. This reaction shows excellent functional group compatibility and can be performed using a number of sterically and electronically different aryl bromides and secondary benzamides.


2019 ◽  
Author(s):  
John Montgomery ◽  
Alexander W. Rand

A new method to access alpha-arylated benzamides has been enabled by metallaphotoredox catalysis. This system allows for non-directed C–H functionalization of N-alkyl benzamides using a dual nickel/iridium catalytic system to form tertiary stereocenters in good enantiomeric excess and moderate yields. This reaction shows excellent functional group compatibility and can be performed using a number of sterically and electronically different aryl bromides and secondary benzamides.


Sensors ◽  
2020 ◽  
Vol 20 (19) ◽  
pp. 5697
Author(s):  
Chang Sun ◽  
Shihong Yue ◽  
Qi Li ◽  
Huaxiang Wang

Component fraction (CF) is one of the most important parameters in multiple-phase flow. Due to the complexity of the solid–liquid two-phase flow, the CF estimation remains unsolved both in scientific research and industrial application for a long time. Electrical resistance tomography (ERT) is an advanced type of conductivity detection technique due to its low-cost, fast-response, non-invasive, and non-radiation characteristics. However, when the existing ERT method is used to measure the CF value in solid–liquid two-phase flow in dredging engineering, there are at least three problems: (1) the dependence of reference distribution whose CF value is zero; (2) the size of the detected objects may be too small to be found by ERT; and (3) there is no efficient way to estimate the effect of artifacts in ERT. In this paper, we proposed a method based on the clustering technique, where a fast-fuzzy clustering algorithm is used to partition the ERT image to three clusters that respond to liquid, solid phases, and their mixtures and artifacts, respectively. The clustering algorithm does not need any reference distribution in the CF estimation. In the case of small solid objects or artifacts, the CF value remains effectively computed by prior information. To validate the new method, a group of typical CF estimations in dredging engineering were implemented. Results show that the new method can effectively overcome the limitations of the existing method, and can provide a practical and more accurate way for CF estimation.


1997 ◽  
Vol 33 (01) ◽  
pp. 65-72 ◽  
Author(s):  
J. T. Korva ◽  
G. A. Forbes

A technique for leaf area measurement utilizing water spray as an inexpensive substitute for electronic equipment was developed and tested with leaves of potato (Solanum tuberosum L.). The leaf areas measured by the spray method were highly correlated with those measured by an electronic area meter. Measurements of leaf area obtained by the spray method were significantly more highly correlated with those obtained by the area meter than were the measurements of dry weights. The main advantages of the new method are precision, accuracy and immediate results at a low cost.


Advertising is a broad concept; in this book, the authors have presented a precise look at its practical domains. Modern advertising has become low-cost with fast access to target users, transferring a persuasive concept to customers and getting a positive behavioral reaction. The last part of their definition is indicative of a new method of advertising, which goes a step further than other methods. A positive reaction embedded in an advertising function comes from advertisers’ use of new communicational practices to transfer and receive messages. The emergence and application of new technology necessitates using the appropriate tools. In this chapter, the authors first define these new tools (strategies). Then, they discuss the differences between online and traditional advertising strategies, and offer an integrated model of Internet advertising strategies. Finally, the authors introduce different kinds of appropriate Internet advertising strategies. The purpose of this chapter is to focus on online advertising strategies and provide a fundamental understanding of their relationship to marketing practices. They examine why firms must use online advertising strategies and give some examples of how online advertising strategies can help companies make sound marketing decisions.


2013 ◽  
Vol 9 (2) ◽  
pp. 36-48
Author(s):  
Qutaiba Ali ◽  
Sahar Lazim

The incredible growth of FPGA capabilities in recent years and the new included features have made them more and more attractive for numerous embedded systems. There is however an important shortcoming concerning security of data and design. Data security implies the protection of the FPGA application in the sense that the data inside the circuit and the data transferred to/from the peripheral circuits during the communication are protected. This paper suggests a new method to support the security of any FPGA platform using network processor technology. Low cost IP2022 UBICOM network processor was used as a security shield in front of any FPGA device. It was supplied with the necessary security methods such as AES ciphering engine, SHA-1, HMAC and an embedded firewall to provide confidentiality, integrity, authenticity, and packets filtering features.


2020 ◽  
Vol 8 (5) ◽  
pp. 2728-2740 ◽  
Author(s):  
Anna Plewa ◽  
Andrzej Kulka ◽  
Emil Hanc ◽  
Wojciech Zając ◽  
Jianguo Sun ◽  
...  

A new method of synthesis of stoichiometric Na2FeM(SO4)3 (M = Fe, Mn, Ni) materials is developed.


2018 ◽  
Vol 42 (9) ◽  
pp. 481-485
Author(s):  
Xiulian Zhang ◽  
Zhicheng Zhang ◽  
Yongbin Xie ◽  
Yujie Jiang ◽  
Ruibo Xu ◽  
...  

A simple and efficient access to arylboronates was achieved with methanol-initiated borylation of aryldiazonium salts. Reduction of aryldiazonium ions by single electron transfer from methanol affords aryl radical species, which undergo a subsequent C–B bond formation with bis(pinacolato)diboron. This highly practical borylation process, which can be carried out on the gram-scale, enjoys operational simplicity as well as mild and catalyst-free conditions.


Author(s):  
John H. Mott ◽  
Zachary A. Marshall ◽  
Mark A. Vandehey ◽  
Mike May ◽  
Darcy M. Bullock

Versatile unmanned aerial system (UAS) platforms have grown significantly in popularity by virtue of their low cost relative to manned aircraft, high performance, and operational simplicity. While the Federal Aviation Administration (FAA) currently regulates the operating altitudes, speeds, weights, pilot qualifications, and locations of drones, a lack of capacity and technology prohibits sufficient enforcement of these restrictions. To assess the frequency and severity of manned and unmanned aircraft separation incidents, and to examine the emerging sensor technology available to facilitate such assessment, flight operations in controlled airspace around Orlando Melbourne International Airport (KMLB) were monitored. One sensor system deployed at KMLB reported UAS locations, altitudes, and flight durations, while a second system reported manned aircraft positions, altitudes, and timestamps using ADS-B signals. Evaluation of flight operations data in the vicinity of KMLB revealed eight potential drone incursions over a 2-week period. Aircraft flight paths were retroactively tracked to map these unmanned and manned aerial conflicts; aircraft identification information was also researched to contextualize the incidents. The frequency and magnitude of identified events suggest the need for additional research to further explore the problem scope and potential solutions.


1964 ◽  
Vol 37 (4) ◽  
pp. 927-933
Author(s):  
J. R. Wolfee ◽  
J. R. Albin

Abstract Ethylene—propylene—nonconjugated diene terpolymers yield vulcanizates of high modulus and tensile strength in the presence of strongly reinforcing fillers. In many applications where low cost, light color, or nonconductivity are required, it is necessary to use poorly reinforcing mineral fillers. The combination of poorly reinforcing mineral filler and amorphous EP terpolymer yields vulcanizates which do not have the excellent stress-strain properties characteristic of many black loaded stocks. The purpose of this paper is to present a new method of obtaining superior properties in mineral filled EP terpolymer vulcanizates.


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