scholarly journals Lewis acidic FeCl3 promoted 2-aza-Cope rearrangement to afford α-substituted homoallylamines in dimethyl carbonate

RSC Advances ◽  
2019 ◽  
Vol 9 (31) ◽  
pp. 18013-18017 ◽  
Author(s):  
Karthik Gadde ◽  
Jonas Daelemans ◽  
Bert U. W. Maes ◽  
Kourosch Abbaspour Tehrani

The current work shows an iron-catalyzed 2-aza-Cope rearrangement in dimethyl carbonate for the synthesis of a wide variety of α-substituted homoallylamines from readily accessible starting materials with diverse functional groups.

2015 ◽  
Vol 15 (3) ◽  
pp. 256-262 ◽  
Author(s):  
Dina Asnawati ◽  
I Made Sudarma ◽  
Emmy Yuanita ◽  
Baiq Fadila Arlina ◽  
Saprini Hamdiani ◽  
...  

Eugenol is a compound with a variety of reactive functional groups such as allyl, hydroxy and methoxy. The presence of the functional groups brings eugenol possible to undertake the transformation into various derivative compounds with diverse activities. One of the simple and possible transformations is methylation or alkylation. Commonly, methyl halides and dimethyl sulphate are used as methylation agent. However, those kinds of methylation agents are toxic and carcinogenic. In this research dimethyl carbonate, an alternative methylation agent is used, because of its low toxicity, green, and economic. The synthesis has been carried out by using a catalyst. Bentonite was activated by heating to a temperature using 300 °C. Methylation was shown by the formation of a light yellow liquid (25.71% yield). The structures of products were characterized by GC-MS and obtained a compound, namely bis eugenol (4-allyl-2-methoxyphenoxy) methane (2.37% yield).


2022 ◽  
Author(s):  
Subhadip De ◽  
Breanna Tomiczek ◽  
Yinuo Yang ◽  
Kenneth Ko ◽  
Ion Ghivirga ◽  
...  

Reported herein is the discovery of a diastereoselective indole-dearomative Cope rearrangement. A suite of minor driving forces (substrate destabilizing effects; product stabilizing effects) are what promote this otherwise unfavorable dearomatization reaction. These include the following that work in concert to overcome the penalty for dearomatization: (i.) steric congestion in the starting material, (ii.) alkylidene malononitrile and stilbene conjugation events in the product, and (iii.) an unexpected intramolecular p–p* stack on the product side of the equilibrium. The key substrates are rapidly assembled from alkylidenemalononitriles and indole-phenylmethanol derivatives resulting in many successful examples (high yields and diastereoselectivity). The products are structurally complex bearing vicinal stereocenters generated by the dearomative Cope rearrangement. They also contain a variety of functional groups for interconversion to complex architectures. On this line, also described herein are proof-of-concept strategies for achieving enantioselectivity and conversion of the dearomative products to valuable and functionalized small drug-like molecules.


1998 ◽  
Vol 3 (4) ◽  
pp. 6-6
Author(s):  
Marc T. Taylor

Abstract This article discusses two important cases that involve the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides). First, in Vargas v Industrial Com’n of Arizona, a claimant had a pre-existing non–work-related injury to his right knee as well as a work-related injury, and the issue was apportionment of the pre-existing injury. The court held that, under Arizona's statute, the impairment from the pre-existing injury should be subtracted from the current work-related impairment. In the second case, Colorado courts addressed the issue of apportionment in a workers’ compensation claim in which the pre-existing injury was asymptomatic at the time of the work-related injury (Askey v Industrial Claim Appeals Office). In this case, the court held that the worker's benefits should not be reduced to account for an asymptomatic pre-existing condition that could not be rated accurately using the AMA Guides. The AMA Guides bases impairment ratings on anatomic or physiologic loss of function, and if an examinee presents with two or more sequential injuries and calculable impairments, the AMA Guides can be used to apportion between pre-existing and subsequent impairments. Courts often use the AMA Guides to decide statutorily determined benefits and are subject to interpretation by courts and administrative bodies whose interpretations may vary from state to state.


2015 ◽  
Vol 20 (3) ◽  
pp. 176-189 ◽  
Author(s):  
John F. Rauthmann

Abstract. There is as yet no consensually agreed-upon situational taxonomy. The current work addresses this issue and reviews extant taxonomic approaches by highlighting a “road map” of six research stations that lead to the observed diversity in taxonomies: (1) theoretical and conceptual guidelines, (2) the “type” of situational information studied, (3) the general taxonomic approach taken, (4) the generation of situation pools, (5) the assessment and rating of situational information, and (6) the statistical analyses of situation data. Current situational taxonomies are difficult to integrate because they follow different paths along these six stations. Some suggestions are given on how to spur integrated taxonomies toward a unified psychology of situations that speaks a common language.


2016 ◽  
Vol 32 (2) ◽  
pp. 155-164 ◽  
Author(s):  
John F. Rauthmann ◽  
Ryne A. Sherman

Abstract. It has been suggested that people perceive psychological characteristics of situations on eight major dimensions ( Rauthmann et al., 2014 ): The “Situational Eight” DIAMONDS (Duty, Intellect, Adversity, Mating, pOsitivity, Negativity, Deception, Sociality). These dimensions have been captured with the 32-item RSQ-8. The current work optimizes the RSQ-8 to derive more economical yet informative and precise scales, captured in the newly developed S8*. Nomological associations of the original RSQ-8 and the S8* with situation cues (extracted from written situation descriptions) were compared. Application areas of the S8* are outlined.


1971 ◽  
Author(s):  
Warren G. Bennis ◽  
Michael Beer ◽  
Gerald R. Pieters ◽  
Alan T. Hundert ◽  
Samuel H. Marcus ◽  
...  

2016 ◽  
Vol 19 (2) ◽  
pp. 93-100
Author(s):  
Lalita El Milla

Scaffolds is three dimensional structure that serves as a framework for bone growth. Natural materials are often used in synthesis of bone tissue engineering scaffolds with respect to compliance with the content of the human body. Among the materials used to make scafffold was hydroxyapatite, alginate and chitosan. Hydroxyapatite powder obtained by mixing phosphoric acid and calcium hydroxide, alginate powders extracted from brown algae and chitosan powder acetylated from crab. The purpose of this study was to examine the functional groups of hydroxyapatite, alginate and chitosan. The method used in this study was laboratory experimental using Fourier Transform Infrared (FTIR) spectroscopy for hydroxyapatite, alginate and chitosan powders. The results indicated the presence of functional groups PO43-, O-H and CO32- in hydroxyapatite. In alginate there were O-H, C=O, COOH and C-O-C functional groups, whereas in chitosan there were O-H, N-H, C=O, C-N, and C-O-C. It was concluded that the third material containing functional groups as found in humans that correspond to the scaffolds material in bone tissue engineering.


1996 ◽  
Vol 451 ◽  
Author(s):  
T. Shimizu ◽  
M. Murahara

ABSTRACTA Fluorocarbon resin surface was selectively modified by irradiation with a ArF laser beam through a thin layer of NaAlO2, B(OH)3, or H2O solution to give a hydrophilic property. As a result, with low fluence, the surface was most effectively modified with the NaAlO2 solution among the three solutions. However, the contact angle in this case changed by 10 degrees as the fluence changed only 1mJ/cm2. When modifying a large area of the surface, high resolution displacement could not be achieved because the laser beam was not uniform in displacing functional groups. Thus, the laser fluence was successfully made uniform by homogenizing the laser beam; the functional groups were replaced on the fluorocarbon resin surface with high resolution, which was successfully modified to be hydrophilic by distributing the laser fluence uniformly.


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