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Joshua thoroughly enjoyed presenting the group's research on "Preassembly-controlled Photoredox Catalysis and Electrophotocatalysis" at the Max Planck Institute for Colloids and Interfaces at Potsdam hosted by their newest member (and now Liebig Fellowship holder!) Dr. John Molloy

Joshua got to meet, and enjoy discussions with rising stars in photo- and flow chemistry that he admires: Dr. Bart Pieber and Dr. Dario Cambie  slide1





Joshua shares some of the group's research at a webinar hosted by scientific instrument (flow reactor) manufacturer H.E.L. Group, alongside former colleague Lee Edwards (GSK), Prof. Russell Taylor and his Ph.D student Samuel Raynes (University Durham) on the topic of hetereogeneous catalysis. Check it out



Our cover image for Shangze's Org. Chem. Front. was selected as one of the outside covers for Issue 6!

Electron deficient arenes queue up to ride the precomplexation merry-go-round, powered by photoelectrochemistry. *Caution* extreme redox potentials, ultrashort lifetimes, breaks Kasha's rule (the organic photochemist interpretation of). 

Not suitable for all riders (1,4-dichlorobenzene, iodobenzene!).

Artist credit to our graphic designer Sarah S. Coutts!)

Check it out: 



Our cover image for Jaspreet's recent Org. Lett. was selected as one of the covers for Issue 6! 

The photochemical SET reaction between electron-rich arenes and persulfate in a solvent cage is illustrated by a cage fight. Cleavage of persulface affords SO4, which reaches for a H atom. TEMPO's inability to inhibit the reaction is illustrated by spectators cheering from outside the cage.

Artist credit to our graphic designer Sarah S. Coutts!

Check it out:OLTOC


After a long peer-review, AK Bärham emerge victorious with the publication of their independent study on triarylamines as tunable, precomplexing, super-oxidizing, Kasha rule-breaking electroactivated PhotoCatalysts! Check it out in Org. Chem. Front. (open access!)

We think that photocatalyst-substrate precomplexation marks the next evolutionary stage in PhotoRedox Catalysis - overturning conventional selectivities and breaking established rules in photochemistry.

Concepts in this manuscript are highly contraversial. *Proceed with caution* You have been warned ;-)




Joshua is honored and humbled to be among the Daimler und Benz Stiftung's Stipendiaten 2021. The scholarship provides funding of 40,000 EUR to support AK Barham's future endeavors in synthetic photoelectrochemistry over the following 2 years!


We welcome SynCat students Wolfgang, Jonathan and Ludwig for research practicums - good luck in your endeavors in synthesis, photoelectrochemistry and flow chemistry!


We welcome Shahboz, who graduated his Master Thesis of the SynCat programme with flying colours, back to AK Bärham as a Ph.D student!

Shahboz came to us in January 2019 with little practical or theoretical experience in organic chemistry. Amazing to see how much he has grown and what he has achieved in just 1 year: 1) He wrote a stellar review on photosensitized C(sp3)-H fluorinations published in Beilstein J. Org. Chem 2) He discovered a new class of photosensitizer during his Thesis, applied it to a broad substrate scope and is close to publication 3) He contributed to a study in AK König which was published in ACS Catalysis 4) He contributed ~30 substrates to a synthetic study under Dr. Xianhai Tian approaching publication


5) He became a father!!! ^_^

Terrific job Shahboz, we are so proud and we look forward to your exciting future research!



Delighted that Jaspreet's Master Thesis work got published in Org. Lett.  Check it out (open access!). Amide C-H arylation with electron-rich arenes can be achieved without the photocatalyst! Mechanistic studies imply an electron-donor-acceptor complex and further reactions taking place in confined space within a "solvent-cage". We are *excited* and curious for the opportunities that preassembly in photocatalysis may offer! SynCat Master student Ahmed Shahin contributed important control reactions and cyclic voltammetry experiments.

Well done to Jaspreet and Ahmed!




Joshua is thrilled to be recognized among the Thieme Chemistry Journal Awardees 2021, alongside other rising stars in organic chemistry and catalysis!

Joshua was even more thrilled to hear this news from one of his idols in organometallic and flow 'flash' chemistry, Prof. Paul Knochel :-)


A collaborative study on heterogeneous graphitic carbon nitride/dual Ni photocatalysis between AK König, AK Bärham and MPI Potsdam, led by Dr. Saikat Das of the König group, was published in ACS Catalysis! 

The reaction demonstrated broad functional group tolerance, a wide substrate scope and could be used in the late-stage functionalization of pharmaceutical molecules. Jaspreet's kinetic studies demonstrated zero-order profiles for this surface adsorption-limited reaction. She evaluated the scalability options, and found that, surprisingly, flow photochemistry was not the way to go due to time-divorced flowing steams of solid and liquid phases. Further studies are needed to identify continuous flow options for this synthetically useful reaction!

Well done Jaspreet, and well done to all involved! 




A Happy New Year to all from AK Bärham!

Like everything.. Christmas was delayed by the pandemic and arrived late; the Bären are pleased to announce their acquisition of a new toy from Corning SAS; a lab flow photoreactor for gas/liquid heterogeneous photochemistry - look forward to taming O2-consuming and N2-evolving reactions in it!

Corning Stockphoto


Thrilled, that Jaspreet who completed her Master Thesis as the very first MSc graduate of the Bärham group (with, let it be known, a top 1.0 grade for her Thesis..), is staying with us for a Ph.D.!! Welcome and may the flow be with you..


Interested in photochemistry, photosensitization, fluorinations or trifluoromethylations? How do small, EUR/kg cheap, 'colourless' organic photosensitizers enable C-F bond formations or trifluoromethylations selectively, up to gram scale with light? Shahboz published a comprehensive overview in Beilstein J. Org. Chem. Terrific effort & congratulations!



Our cover image for Mark and Michal's Org. Biomol. Chem. was selected for the outside front cover of Issue 39! 

The amide enolate and styrene get married in a metal-ene transition state by 'vicar' potassium atop the wedding CAKES (C-Alkylation of K Enolates with Styrenes). The knife of mechanistic studies dissects the reaction mechanism. Meanwhile the benzylate are dimethylphenylvinylsilane make for a quick 'reactive' getaway to catch a CAB (C-Alkylation of Benzylates)

Artist credit to our graphic designer Sarah S. Coutts!

Check it out:



Our review, "C-alkylations of Alkali Metal Carbanions with Olefins" (CAMCOs) is published in Org. Biomol. Chem. It covers the historical perspective, contemporary applications and developing mechanistic understanding of this bizarre class of reactions.

Proud of Mark and Michafor their superb lockdown efforts.



Our Auto-Frequency Tunable (AFT) Microwave Flow Reactors (100 W, 0.8-9.9 mL/min = top; 250 W, 0.8-50.0 mL/min = bottom) from SAIDA FDS Inc. have survived a long journey at sea and arrived safely in Regensburg!

Look forward to doing some high temp. high productivity reactions!


Our Vapourtec UV-150 photo-flow reactor complete with slurry-capable V3 peristaltic pumps and flow-commander software has arrived! Lets get that photochem scaled up to useful quantities :-]


We welcome Dr. Xianhai Tian to the group! Dr. Tian graduated with his Ph.D. in Chemistry from Prof. Dr. Stephen Hashmi's group in Heidelburg.


Our ElectraSyn2.0 Pro's complete with Carousel modules have arrived! Time to electrify some organic synthesis... :-]



We welcome Dr. Shangze Wu to the group! Dr. Wu joins us after completing his postdoctoral reasearch in Prof. Dr. Andreas Gansäuer's group in Bonn. Dr. Wu graduated with his Ph.D. in Chemistry from Zhejiang University under the supervision of Prof. Dr. Shengming Ma.

  1. Fakulty of Chemistry and Pharmacy
  2. Institute of Organic Chemistry

Joshua Barham



Sofja Kovalevskaja Group Leader

Office: CH 23.2.80

Phone +49 (0)941 943-4373