scholarly journals Unlocking the Catalytic Hydrogenolysis of Chlorosilanes into Hydrosilanes with Superbases

Author(s):  
Gabriel Durin ◽  
Jean-Claude Berthet ◽  
Emmanuel Nicolas ◽  
Thibault Cantat

The efficient synthesis of hydrosilanes by catalytic ydrogenolysis of chlorosilanes is described, using an Iridum (III) pincer catalyst. A careful selection of a nitrogen base (incl. sterically hindered guanidines and phosphazenes) can unlock the preparation of Me<sub>3</sub>SiH, Et<sub>3</sub>SiH and Me<sub>2</sub>SiHCl in high yield (up to 98%), directly from their corresponding chlorosilanes.

2021 ◽  
Author(s):  
Gabriel Durin ◽  
Jean-Claude Berthet ◽  
Emmanuel Nicolas ◽  
Thibault Cantat

The efficient synthesis of hydrosilanes by catalytic ydrogenolysis of chlorosilanes is described, using an Iridum (III) pincer catalyst. A careful selection of a nitrogen base (incl. sterically hindered guanidines and phosphazenes) can unlock the preparation of Me<sub>3</sub>SiH, Et<sub>3</sub>SiH and Me<sub>2</sub>SiHCl in high yield (up to 98%), directly from their corresponding chlorosilanes.


Author(s):  
Janice L. Waldron ◽  
Stephanie Horsley ◽  
Kari K. Veblen

We all feel the implications of the force of social media—for good and for ill—in our lives and in our professional world. At the time of this writing, Facebook continues with its struggle to “clean up its act” as more revelations surrounding breaches of trust and hacked user data surface in the news and various countries attempt to hold Facebook to account. Despite this, social media use continues to grow exponentially, and the potential for responsible, ethical, and transparent social media to transform the ways in which we interact with and learn from each other increase with it. As we wait to see what the future holds for social media in society, we are reminded once again that it is the careful selection of pedagogical tools such as social media, as well the guided awareness of the challenges and benefits of those tools, that remains constant, even as tools may change, disappear, or fall out of fashion.


2021 ◽  
Vol 13 (15) ◽  
pp. 8247
Author(s):  
Dimitrios N. Vlachostergios ◽  
Christos Noulas ◽  
Anastasia Kargiotidou ◽  
Dimitrios Baxevanos ◽  
Evangelia Tigka ◽  
...  

Lentil is a versatile and profitable pulse crop with high nutritional food and feed values. The objectives of the study were to determine suitable locations for high yield and quality in terms of production and/or breeding, and to identify promising genotypes. For this reason, five lentil genotypes were evaluated in a multi-location network consisting of ten diverse sites for two consecutive growing seasons, for seed yield (SY), other agronomic traits, crude protein (CP), cooking time (CT) and crude protein yield (CPY). A significant diversification and specialization of the locations was identified with regards to SY, CP, CT and CPY. Different locations showed optimal values for each trait. Locations E4 and E3, followed by E10, were “ideal” for SY; locations E1, E3 and E7 were ideal for high CP; and the “ideal” locations for CT were E3 and E5, followed by E2. Therefore, the scope of the cultivation determined the optimum locations for lentil cultivation. The GGE-biplot analysis revealed different discriminating abilities and representativeness among the locations for the identification of the most productive and stable genotypes. Location E3 (Orestiada, Region of Thrace) was recognized as being optimal for lentil breeding, as it was the “ideal” or close to “ideal” for the selection of superior genotypes for SY, CP, CT and CPY. Adaptable genotypes (cv. Dimitra, Samos) showed a high SY along with excellent values for CP, CT and CPY, and are suggested either for cultivation in many regions or to be exploited in breeding programs.


Author(s):  
Tamás Hergert ◽  
Béla Mátravölgyi ◽  
Róbert Örkényi ◽  
János Éles ◽  
Ferenc Faigl

AbstractA three-step batch-flow hybrid process has been developed for an expeditious synthesis of the enynol key intermediate of antifungal terbinafine. This procedure involves consecutive organometallic steps without the necessity of any in-line purification: after a metalation by n-butyllithium, a selective addition of the lithium salt was elaborated followed by a Grignard reaction resulting in a high yield of 6,6-dimethylhept-1-en-4-yn-3-ol. Moreover, as an alternative to tetrahydrofuran, cyclopentyl methyl ether was used as solvent implementing a safe, sustainable, yet selective synthetic process. Even on a laboratory-scale, the optimized batch-flow hybrid process had a theoretical throughput of 41 g/h. Furthermore, the newly developed process provides an efficient synthesis route to the key-intermediate, while making acrolein obsolete, minimizing side-products, and enabling safe and convenient scale-up.


Lab on a Chip ◽  
2021 ◽  
Author(s):  
Mohammad Simchi ◽  
Jason Riordon ◽  
Jae Bem You ◽  
Yihe Wang ◽  
Sa Xiao ◽  
...  

A 3D-structured sperm selection device is presented that achieves both high selectivity and high yield via thousands of parallel channels. The device significantly outperforms the best clinical practice by selecting ∼100 000 of higher-quality sperm.


2019 ◽  
Vol 21 (1) ◽  
pp. 165 ◽  
Author(s):  
Dennis N. Lozada ◽  
Jayfred V. Godoy ◽  
Brian P. Ward ◽  
Arron H. Carter

Secondary traits from high-throughput phenotyping could be used to select for complex target traits to accelerate plant breeding and increase genetic gains. This study aimed to evaluate the potential of using spectral reflectance indices (SRI) for indirect selection of winter-wheat lines with high yield potential and to assess the effects of including secondary traits on the prediction accuracy for yield. A total of five SRIs were measured in a diversity panel, and F5 and doubled haploid wheat breeding populations planted between 2015 and 2018 in Lind and Pullman, WA. The winter-wheat panels were genotyped with 11,089 genotyping-by-sequencing derived markers. Spectral traits showed moderate to high phenotypic and genetic correlations, indicating their potential for indirect selection of lines with high yield potential. Inclusion of correlated spectral traits in genomic prediction models resulted in significant (p < 0.001) improvement in prediction accuracy for yield. Relatedness between training and test populations and heritability were among the principal factors affecting accuracy. Our results demonstrate the potential of using spectral indices as proxy measurements for selecting lines with increased yield potential and for improving prediction accuracy to increase genetic gains for complex traits in US Pacific Northwest winter wheat.


Antiquity ◽  
2014 ◽  
Vol 88 (340) ◽  
pp. 378-394 ◽  
Author(s):  
N.I. Shishlina ◽  
D.S. Kovalev ◽  
E.R. Ibragimova

The origin and development of wheeled vehicles continues to fascinate today no less than when Stuart Piggott (1974) first wrote about the subject inAntiquity40 years ago. A growing number of examples from the steppes of southern Russia and Ukraine are providing new insights into the design and construction of these complex artefacts. A recent example from the Ulan IV burial mound illustrates the techniques employed and the mastery of materials, with careful selection of the kinds of wood used for the wheels, axles and other elements. Stable isotope analysis of the individual interred in this grave showed that he had travelled widely, emphasising the mobility of steppe populations.


2012 ◽  
Vol 90 (11) ◽  
pp. 965-974 ◽  
Author(s):  
Stefan Roesner ◽  
Varinder K. Aggarwal

The synthesis of the pharmaceutical (R)-tolterodine is reported using lithiation/borylation–protodeboronation of a homoallyl carbamate as the key step. This step was tested with two permutations: an electron-neutral aryl Li-carbamate reacting with an electron-rich boronic ester and an electron-rich aryl Li-carbamate reacting with an electron-neutral boronic ester. It was found that the latter arrangement was considerably better than the former. Further improvements were achieved using magnesium bromide in methanol leading to a process that gave high yield and high enantioselectivity in the lithiation/borylation reaction. The key step was used in an efficient synthesis of (R)-tolterodine in a total of eight steps in a 30% overall yield and 90% ee.


2021 ◽  
Vol 13 (5) ◽  
pp. 2863
Author(s):  
Kaowen Grace Chang ◽  
Hungju Chien

Forcipomyia taiwana, a bloodsucking midge that is one of the most irritating biting pests in Taiwan, has raised widespread public concern. However, we have little information about the extent to which landscape factors affect their potential habitats. As a result, landscape professionals do not have enough information to implement preventive strategies to control midges. The purpose of this study is to investigate the relationship between landscaping and algae growth for larval breeding sites of Forcipomyia taiwana. The intent is to determine the environmental strategies that make the planned landscape unsuitable for midges to breed. GIS based on data collected from 16 constructed landscape sites (317,187 m2 in total) was utilized to spatially examine the relationship between the occurrence of the algae for midge breeding sites and the ground surface types and planting characteristics in each landscape. The results revealed that the potential midge habitats can be controlled through careful selection of the ground surface, the improvement of the site drainage, and choosing plants with the appropriate characteristics. Apart from choosing the appropriate type of paving surface, the integrity of the paving installation and the coverage of the ecological surface also influence prevention efficacy.


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