The optimization, intensification, and scale-up of photochemical processes constitute a particular challenge in manufacturing environment geared primarily toward thermal chemistry. In this work, we present versatile flow-based robotic platform to address these challenges through the integration readily available hardware custom software. Our open-source combines liquid handler, syringe pumps, tunable continuous-flow photoreactor, inexpensive Internet Things devices, an in-line benchtop...

Abstract Ruthenium–triphos complexes exhibited unprecedented catalytic activity and selectivity in the redox‐neutral CC bond cleavage of β‐O‐4 lignin linkage 1,3‐dilignol model compounds. A mechanistic pathway involving a dehydrogenation‐initiated retro‐aldol reaction for was proposed line with experimental data DFT calculations.

Dual function of catalyst: Both regio- and enantioselectivity are dictated by Cu catalysis using the reversed josiphos ligand. This allows enantioselective 1,6-addition Grignard reagents to acyclic α,β,γ,δ-unsaturated esters monosubstituted at β δ positions (see scheme). Supporting information for this article is available on WWW under http://www.wiley-vch.de/contents/jc_2002/2008/z703702_s.pdf or from author. Please note: The publisher not responsible content functionality any supporting...

Cu-TolBINAP-catalyzed conjugate addition of Grignard reagents to 4-chloro-α,β-unsaturated esters, thioesters, and ketones leads 4-chloro-3-alkyl-substituted thioesters in up 84% yield 96% ee upon protonation the corresponding enolates at low temperature. Tandem addition-enolate trapping, however, yields trans-1-alkyl-2-substituted cyclopropanes 92% 98% ee. The versatility this reaction is illustrated by formation key intermediates for formal syntheses cascarillic acid grenadamide.

N-ethyl riboflavin efficiently catalyzes the hydrazine mediated reduction of carbon−carbon double bonds. This strategy allows chemo-selective reductions in complex molecules that are prone to racemization, olefin isomerization, or hydrogenolysis transition metal-catalyzed hydrogenations. The high functional group tolerance this methodology is demonstrated as well.

The enantioselective 1,6-addition to unsaturated carbonyl compounds offers unique opportunities study the range of selectivities one can obtain using Cu catalysis. Here, a substrate–reagent approach structural information on mechanism extended conjugate additions is reported. By studying influence several halides in Grignard reagent and source 1,6-addition, it was shown that advantageous use combination EtMgBr as CuI source. Furthermore, exploring substrates bearing alkyl esters revealed...

Nickel was identified as a catalyst for the cyclopropanation of unactivated olefins by using in situ generated lithiomethyl trimethylammonium triflate methylene donor. A mechanistic hypothesis is proposed which generation reactive nickel carbene explains several interesting observations. Additionally, our findings shed light on report Franzen and Wittig published 1960 that had been retracted later owing to irreproducibility, provide rational basis systematic development reaction preparative...

Abstract The highly enantioselective synthesis of α‐methyl‐substituted esters is reported in up to 90% yield and 99% ee using copper‐TaniaPhos as chiral catalyst. transformation proved scalable at least 6.6 mmol (1.7 g scale). products this have been further elaborated multifunctional building blocks with a single (branched acids) or multiple stereogenic centers (vicinal dimethyl esters, well as, hydroxy‐ iodo‐substituted lactones).

Methane, which has a high energy storage density and is safely stored transported in our existing infrastructure, can be produced through conversion of the undesired carrier H2 with CO2. Methane production standard transition-metal catalysts requires high-temperature activation (300-500 °C). Alternatively, semiconductor metal oxide photocatalysts used, but they require high-intensity UV light. Here, we report Ru catalyst that facilitates methanation below 250 °C using sunlight as an source....

Doppelte Funktion: Der katalytische Kupferkomplex des „inversen“ Josiphos-Liganden bestimmt sowohl die Regio- als auch Enantioselektivität der Titelreaktion. Damit gelingt eine enantioselektive 1,6-Addition von Grignard-Reagentien an acyclische α,β,γ,δ-ungesättigte Ester, β- und δ-Position einfach substituiert sind (siehe Schema).

Abstract Ruthenium–triphos complexes exhibited unprecedented catalytic activity and selectivity in the redox‐neutral CC bond cleavage of β‐O‐4 lignin linkage 1,3‐dilignol model compounds. A mechanistic pathway involving a dehydrogenation‐initiated retro‐aldol reaction for was proposed line with experimental data DFT calculations.

Abstract Plasmon catalysis is an interesting technology concept for powering chemical processes with light. Here, we report the use of various Al 2 O 3 ‐supported Ru spheroidal nanoparticles as catalyst low‐temperature conversion CO and H to CH 4 (Sabatier reaction), using sunlight energy source. At high loadings (5.9 % w/w), observe a sharp increase in rate powered reaction when compared dark at same bed temperature. Based on our results exclude plasmon coupling cause, attribute enhancement...

Abstract Sunlight‐powered reduction of CO 2 to fuels and chemicals is a promising strategy close the carbon loop facilitate energy transition. In this research, we demonstrate that Au nanoparticles supported on TiO are an efficient plasmonic catalyst for sunlight‐powered reverse water‐gas shift (rWGS) reaction. A maximum production rate 429 mmol ⋅ g −1 h with selectivity 98 % apparent quantum efficiency 4.7 were achieved using mildly concentrated sunlight (1.44 W cm −2 equals 14.4 sun). The...

A Phytophthora mating hormone with an array of 1,5-stereogenic centers has been synthesized by using our recently developed methodology catalytic enantioselective conjugate addition Grignard reagents. We applied this in a diastereo- and iterative route obtained two the 16 possible stereoisomers α1. These synthetic induced formation sexual spores (oospores) A2 type strains three heterothallic species, P. infestans , capsici nicotianae but not A1 strains. The response was...

Methylenation of electron-rich olefins is a highly challenging reaction, for which we have developed new methodology exploiting Pd-catalysis and halomethylboronate reagents, the latter replacing diazomethane zinc carbenoids as methylene donors. Optimization reaction norbornene extension to several other are reported, with reasonable-to-excellent yields cyclopropanes in combination β-H elimination products. Several mechanisms plausible this methylenation reaction.

Continuous-flow methodologies offer promising avenues for sustainable processing due to their precise process control, scalability, and efficient heat mass transfer. The small dimensions of continuous-flow reactors render them highly suitable light-assisted reactions, as can be encountered in carbon dioxide hydrogenations. In this study, we present a novel reactor system emphasizing reproducibility, modularity, automation, facilitating streamlined screening conditions catalysts these...

Soluble lithiomethyl trimethylammonium triflate can cyclopropanate styrenes and stilbenes efficiently. Kinetic experiments support a carbolithiation-ring closure mechanism.

Abstract Distinguishing between photothermal and non‐thermal contributions is essential in plasmon catalysis. Use of a tailored optical temperature sensor based on fiber Bragg gratings enabled us to obtain an accurate map illuminated plasmonic catalyst bed with high spatiotemporal resolution. Its importance for quantification the catalysis demonstrated using Ru/Al 2 O 3 catalyst. Upon illumination LEDs, we measured differences exceeding 50 °C top 0.5 mm bed. Furthermore, discovered surface...

Straightforward deprotonation of soluble tetramethylammonium salts with alkyllithium reagents gives lithiomethyl trimethylammonium reagents. Coordination the Li cation is crucial to stability these 'N-C ylides'. These were used prepare epoxides, aziridines and allylic alcohols.

Abstract Nickel wurde als Katalysator für die Cyclopropanierung von unaktivierten Olefinen durch in situ hergestelltes Lithiomethyltrimethylammoniumtriflat Methylendonor identifiziert. Eine mechanistische Hypothese wird vorgeschlagen, welche Entstehung eines reaktiven Nickelcarben beinhaltet, um einige interessante Beobachtungen zu erklären. Zudem beleuchten unsere Resultate einen Bericht Franzen und Wittig aus dem Jahre 1960, der später wegen Irreproduzierbarkeit zurückgezogen wurde,...

The optimization, intensification, and scaling up of chemical processes are essential time-consuming aspects contemporary manufacturing, necessitating expertise precision due to their intricate sensitive nature. However, these process development problems often carried out independently consecutively, which can exacerbate the already significant consumption time resources involved in process. In this work, we present a versatile, all-in-one robotic platform for autonomous photocatalytic...

A modular, automated photoreactor system for CO 2 hydrogenation enables precise conversion into methane or carbon monoxide. The monoxide is subsequently utilized in carbonylation reactions, advancing sustainable synthesis and utilization.