76 research outputs found
Non-enantioselective and enantioselective synthetic transformations using copper and iron salts for diazo insertion reactions into SiâH and SâH bonds and hydrosilylation reactions of ketones
Cette thĂšse dĂ©crit la dĂ©couverte de transformations synthĂ©tiques Ă©nantiosĂ©lectives et non Ă©nantiosĂ©lectives dans lesquelles des catalyseurs chiraux et environnementalement bĂ©nins Ă base de cuivre, de fer et de zinc sont utilisĂ©s pour des rĂ©actions dâinsertion de diazos dans les liaisons SiâH et SâH et pour des rĂ©actions dâhydrosilylation de cĂ©tones. Des rĂ©actions Ă©nantiosĂ©lectives et non Ă©nantiosĂ©lectives dâinsertion de mĂ©tal-carbĂšnes dâα-diazoesters catalysĂ©es par le cuivre et le fer dans les liaisons SiâH et SâH sont dĂ©crites. Nous avons rĂ©ussi Ă dĂ©velopper un protocole efficace pour la rĂ©action dâinsertion de mĂ©tal-carbĂšnes dâα-diazoesters catalysĂ©e par le cuivre et le fer dans les liaisons SiâH et SâH. Avec lâutilisation de [(MeCN)4Cu]PF6 et de Fe(OTf)2, une grande variĂ©tĂ© dâα-silylesters ont Ă©tĂ© synthĂ©tisĂ©s avec des bons et des excellents rendements (jusquâĂ 98%). Ces catalyseurs peuvent aussi ĂȘtre utilisĂ©s efficacement pour lâinsertion de mĂ©tal-carbĂšne dans la liaison Sâ H avec des bons rendements (jusquâĂ 90%). Des rĂ©sultats prometteurs ont Ă©tĂ© obtenus pour les rĂ©actions dâinsertion de mĂ©tal-carbĂšnes dâα-diazoesters catalysĂ©es par le fer dans la liaison SiâH avec lâutilisation du DMC comme solvant vert en remplacement de CH2Cl2. Plusieurs ligands diamines chiraux ont Ă©tĂ© testĂ©s pour dĂ©velopper une rĂ©action dâinsertion de mĂ©tal-carbĂšne hautement Ă©nantiosĂ©lective dans la liaison SiâH avec lâutilisation du sel de cuivre peu coĂ»teux [(MeCN)4Cu]PF6 comme catalyseur. Un excellent rendement ainsi quâune excellente Ă©nantiosĂ©lectivitĂ© (rendement de 85%, 99:1 er) ont Ă©tĂ© obtenus lorsque les ligands contenant un coeur (R, R)-diaminocyclohexane et des groupements mĂ©sityles ont Ă©tĂ© utilisĂ©s. Il sâagit dâun trĂšs bon exemple de rĂ©action hautement Ă©nantiosĂ©lective dâinsertion dans la liaison SiâH avec lâutilisation dâaryldiazoacĂ©tates, de sources de silane peu coĂ»teuses en comparaison avec dâautres et de ligands diamines chiraux facilement synthĂ©tisables ayant Ă©tĂ© utilisĂ©s pour la premiĂšre fois dans la rĂ©action dâinsertion Ă©nantiosĂ©lective de mĂ©tal-carbĂšne dans la liaison SiâH. Nous avons dĂ©couvert que les diamines chirales, facilement disponibles, sont aussi des ligands efficaces pour la rĂ©duction dâaryle-cĂ©tones avec le catalyseur Zn(OAc)2. Les alcools recherchĂ©s ont Ă©tĂ© obtenus avec des hauts rendements et de trĂšs bons rapports Ă©nantiomĂ©riques (rendements jusquâĂ 99%, er jusquâĂ 99:1). Nous avons aussi obtenu de bons rĂ©sultats pour lâhydrosilylation de la pphĂ©nyltrifluoroacetophĂ©none avec lâutilisation dâun systĂšme bipybox-iPr/Fe(OAc)2...This thesis describes the development of non-enantioselective and enantioselective synthetic transformations using copper, iron, and zinc salts as environmentally benign catalysts for diazo insertion reactions into the SiâH and SâH bonds and hydrosilylation reactions of ketones. Non-enantioselective and enantioselective copper and iron-catalyzed metal carbene insertion reactions of α-diazoesters into SiâH and SâH bonds are described. We successfully developed an efficient copper and iron-catalyzed protocol for the metal carbene insertion reaction of α-diazoesters into SiâH and SâH bonds. By using [(MeCN)4Cu]PF6 and Fe(OTf)2, a wide range of α-silylesters were synthesized in good to excellent yields (up to 98%). These catalysts have been shown to be efficient for metal carbene insertion into SâH bond in high yields (up to 90%) as well. Excellet results have been obtained for iron-catalyzed carbene insertion reactions of α-diazoesters into SiâH bond using DMC as a green solvent instead of CH2Cl2. Several chiral diamine ligands were tested to develop a highly enantioselective metal carbene insertion reaction into the SiâH bond using the inexpensive copper salt [(MeCN)4Cu]PF6 as catalyst. Excellent yield and enantioselectivity (85% yield, 99:1 er) were obtained when the ligands containing a (R, R)- diaminocyclohexane core and mesityl groups were used. This is the very good example of highly enantioselective SiâH bond insertion reactions using aryldiazoacetates and inexpensive silane sources compare to others and easy-to-synthesize chiral diamine ligands that have been used for the first time for enantioselective SiâH bond insertion reaction. We have found that the readily available chiral diamines are also efficient ligands for the reduction of aryl ketones using Zn(OAc)2 as catalyst. The desired alcohols were obtained in high yields and very good enantiomeric ratios (up to 99% yields, up to 99:1 er). We also obtained good results for the hydrosilylation of p-phenyltrifluoroacetophenone using a bipybox-iPr/Fe(OAc)2 system (85% yield, 80:20 er). Based on the information in the literature, there are just a few examples on asymmetric hydrosilylation of pphenyltrifluoroacetophenone using ZnEt2 with very low enantioselectivities
Fe(OTf)2-catalyzed thia-Michael addition reaction : a green synthetic approach to ÎČ-thioethers
A convenient Fe(OTf)2âcatalyzed Michael addition reaction of thiols to α,ÎČâunsaturated carbonyl compounds was developed. The use of a simple procedure (EtOH, room temperature, air atmosphere) allowed to set up effective green catalytic conditions for the CâS bond formation. The scope of the reaction was demonstrated using various substituted thiols and original Michael acceptors. The corresponding ÎČâthioethers were obtained in good to excellent yields (up to 99%). Also, the derivatization into the oneâpot thiaâMichael addition/oxidation reaction of 3â(3â(phenylthio)butanoyl)oxazolidinâ2âone using H2O2 has proven to be efficient
New chiral bis(oxazolinyl)bipyridine ligands and application in the iron catalyzed asymmetric hydrosilylation of ketones
C2 symmetrical 6,6âČ-bis(oxazolinyl)-2,2âČ-bipyridine (bipybox) chiral ligands have been synthesized from readily available 2,2âČ-bipyridine. Catalytic asymmetric hydrosilylation of ketones was studied using this family of ligands in the presence of iron(II) acetate
Copper-catalyzed carbenoid insertion reactions of a-diazoesters and a-diazoketones into SiâH and SâH bonds
An efficient copper-catalyzed carbenoid insertion reaction of a-diazo carbonyl compounds into SiâH and SâH bonds was developed. A wide range of a-silylesters and a-thioesters was obtained in high yields (up to 98%) from a-diazoesters using 5 mol % of a simple copper(I) salt as catalyst. Using 0.05 mol % of the same catalyst, a-diazoketones led to a-silylketones in low to good yields (up to 70%)
Detection and Physical Interaction with Deformable Linear Objects
Deformable linear objects (e.g., cables, ropes, and threads) commonly appear
in our everyday lives. However, perception of these objects and the study of
physical interaction with them is still a growing area. There have already been
successful methods to model and track deformable linear objects. However, the
number of methods that can automatically extract the initial conditions in
non-trivial situations for these methods has been limited, and they have been
introduced to the community only recently. On the other hand, while physical
interaction with these objects has been done with ground manipulators, there
have not been any studies on physical interaction and manipulation of the
deformable linear object with aerial robots.
This workshop describes our recent work on detecting deformable linear
objects, which uses the segmentation output of the existing methods to provide
the initialization required by the tracking methods automatically. It works
with crossings and can fill the gaps and occlusions in the segmentation and
output the model desirable for physical interaction and simulation. Then we
present our work on using the method for tasks such as routing and manipulation
with the ground and aerial robots. We discuss our feasibility analysis on
extending the physical interaction with these objects to aerial manipulation
applications.Comment: Presented at ICRA 2022 2nd Workshop on Representing and Manipulating
Deformable Objects (https://deformable-workshop.github.io/icra2022/
UAS Simulator for Modeling, Analysis and Control in Free Flight and Physical Interaction
This paper presents the ARCAD simulator for the rapid development of Unmanned
Aerial Systems (UAS), including underactuated and fully-actuated multirotors,
fixed-wing aircraft, and Vertical Take-Off and Landing (VTOL) hybrid vehicles.
The simulator is designed to accelerate these aircraft's modeling and control
design. It provides various analyses of the design and operation, such as
wrench-set computation, controller response, and flight optimization. In
addition to simulating free flight, it can simulate the physical interaction of
the aircraft with its environment. The simulator is written in MATLAB to allow
rapid prototyping and is capable of generating graphical visualization of the
aircraft and the environment in addition to generating the desired plots. It
has been used to develop several real-world multirotor and VTOL applications.
The source code is available at
https://github.com/keipour/aircraft-simulator-matlab.Comment: In proceedings of the 2023 AIAA SciTech Forum, Session: Air and Space
Vehicle Dynamics, Systems, and Environments II
New chiral bis(oxazolinyl) bipyridine ligands and application in the iron catalyzed asymmetric hydrosilylation of ketones
C2 symmetrical 6,6'-bis(oxazolinyl)-2,2'-bipyridine (bipybox) chiral ligands have been synthesized from readily available 2,2'-bipyridine. Catalytic asymmetric hydrosilylation of ketones was studied using this family of ligands in the presence of iron(II) acetate
Demonstrating Large-Scale Package Manipulation via Learned Metrics of Pick Success
Automating warehouse operations can reduce logistics overhead costs,
ultimately driving down the final price for consumers, increasing the speed of
delivery, and enhancing the resiliency to workforce fluctuations. The past few
years have seen increased interest in automating such repeated tasks but mostly
in controlled settings. Tasks such as picking objects from unstructured,
cluttered piles have only recently become robust enough for large-scale
deployment with minimal human intervention.
This paper demonstrates a large-scale package manipulation from unstructured
piles in Amazon Robotics' Robot Induction (Robin) fleet, which utilizes a pick
success predictor trained on real production data. Specifically, the system was
trained on over 394K picks. It is used for singulating up to 5 million packages
per day and has manipulated over 200 million packages during this paper's
evaluation period.
The developed learned pick quality measure ranks various pick alternatives in
real-time and prioritizes the most promising ones for execution. The pick
success predictor aims to estimate from prior experience the success
probability of a desired pick by the deployed industrial robotic arms in
cluttered scenes containing deformable and rigid objects with partially known
properties. It is a shallow machine learning model, which allows us to evaluate
which features are most important for the prediction. An online pick ranker
leverages the learned success predictor to prioritize the most promising picks
for the robotic arm, which are then assessed for collision avoidance. This
learned ranking process is demonstrated to overcome the limitations and
outperform the performance of manually engineered and heuristic alternatives.
To the best of the authors' knowledge, this paper presents the first
large-scale deployment of learned pick quality estimation methods in a real
production system.Comment: Robotics: Science and Systems (RSS 2023) conference, July 10 - 14,
2023, Daegu, Republic of Kore
Pick Planning Strategies for Large-Scale Package Manipulation
Automating warehouse operations can reduce logistics overhead costs,
ultimately driving down the final price for consumers, increasing the speed of
delivery, and enhancing the resiliency to market fluctuations.
This extended abstract showcases a large-scale package manipulation from
unstructured piles in Amazon Robotics' Robot Induction (Robin) fleet, which is
used for picking and singulating up to 6 million packages per day and so far
has manipulated over 2 billion packages. It describes the various heuristic
methods developed over time and their successor, which utilizes a pick success
predictor trained on real production data.
To the best of the authors' knowledge, this work is the first large-scale
deployment of learned pick quality estimation methods in a real production
system.Comment: 2023 IEEE/RSJ International Conference on Intelligent Robots and
Systems (IROS), Learning Meets Model-based Methods for Manipulation and
Grasping Worksho
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