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Romero reports (relatively) brisk breakdown of B2Pin2

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Citation:  Hatcher, W.; Vanaparthi, S.; Young, M.; Romero, E. Contrary to Popular Belief, B2pin2 is Not Air Stable. Chemrxiv.  Link to paper: https://chemrxiv.org/doi/full/10.26434/chemrxiv-2025-rxj84 Summary Figure:   Background: Thanks to the massive synthetic utility of the Suzuki-Miyaura coupling for making C-C bonds, borylated arenes are some of the most useful synthetic building blocks you can find. Personally, every lab I have been in has had some library of aryl boronic acids available. Arylboronic acids are a great way to quickly bang out a substrate scope, by attaching different heterocycles or functionalized arenes to a general substrate to evaluate functional group compatibility.    Meanwhile, if you would like to make your own borylated arenes, there are two main established methods- Miyaura borylation and Hartwig-Smith borylation.  Miyaura borylation is a Pd-catalyzed cross-coupling between a sp2-halide and B2pin2 (or related bis-boron compoun...
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Seeman surveys scientists' esteem for structural determination of strychine: Robinson or Woodward?

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 Citation:  Seeman, J. I.; House, M. C. "For Its Size, the Most Complex Natural Product Known." Who Deserves Credit for Determining the Structure of Strychnine?  ACS Cent. Sci.  2022 ,  8 , 672-681.  Before reading the rest of this post, read the following question: Professor A published the correct structure for a natural product.  Six months later, Professor A characterized his correct structure as “inadequate” and “questionable” and stated “feasible alternatives of a more complicated character have been devised.” He then published an alternative (and wrong) structure which he characterized as “the best working hypothesis at present available.”  Shortly thereafter, Professor A changed his mind again, writing “we revert, as the best hypothesis to guide future work, to an earlier [and correct] structure... Several slight modifications of this structure are feasible, and these have special advantages and disadvantages, which must be discus...
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SmI2, "A Reagent Reborn" Notes from a mini-review by Procter

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Citation: Mansell, J. I.; Romano, C.; Procter, D. J. Contemporary Strategies in SmI2 Catalysis: A Reagent Reborn.  Angew. Chem. Int. Ed.  2025 , e202519678.  Been trying to write this post for a few weeks but stuck on writer's block.  Summary Figure:    Introduction  While you wouldn't necessarily expect one particular lanthanide to be a workhorse organic reagent, samarium diiodide (SmI2) has become one of the most common synthetic reagents for a number of radical-related reactions, ranging from reductions of carbonyls or alkyl halides to more complicated bond forming reactions. SmI2 is fairly simple to make (which is good, because it often performs better when freshly prepared) and can be used catalytically or stoichiometrically. Most reactions are done stoichiometrically (SmI2 is cheap enough), but methods that use SmI2 catalytically are interesting both from a sustainability perspective and a reactivity perspective- how do you regenerate your Sm2+ f...
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Prokopchuk pins Palladium's activity on increased C-H acidification compared to Nickel

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Citation: Lin, L.; Schramm, T. K.; Kucheryavy, P.; Lalancette, R. A.; Hansen, A.; Prokopchuk, D. E.  J. Am. Chem. Soc.  2025 ,  ASAP.   https://pubs.acs.org/doi/10.1021/jacs.5c07649 Summary Figure:    Background: C-H functionalization reactions take unactivated carbon-hydrogen bonds (i.e., not very acidic, so not your average enolate) and typically use a transition metal to pull off that hydrogen. Theoretically, "any reaction that activates a carbon-hydrogen bond and makes a product" is an immensely wide net, so for the purposes of analyzing this paper, we'll restrict that towards organometallic reactions that end up forming a carbon-metal bond from a carbon-hydrogen bond.  The paper has a really great introduction to the field, which I will briefly summarize, but I recommend reading through the second paragraph as it is well written. Palladium (and nickel, and other transition metals) often activate C-H bond through a directing group strategy. No...
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Sigman and AbbVie advance B.H. amination by analyzing bulky ligands

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Citation: Ickes, A. R.; Liles, J. P.; Borlinghaus, N.; Henle, J.; Swiatowiec, R.; Kaushik, N. P.; Braje, W. M.; Harper, K. C.; Shekhar, S.; Sigman, M. S.   Leveraging Data Science to Elucidate Ligand Features for Pd-Catalyzed Enantioretentive  N -Arylations of cyclic a-Substituted Amines in Aqueous Media.  J. Am. Chem. Soc.  ASAP. https://pubs.acs.org/doi/10.1021/jacs.5c07224 Summary Figure:   Background: To my best approximation, Buchwald-Hartwig aminations (or N-Arylation with Ar-X like Ullmann couplings) make up about 6% of all reactions medicinal chemists run (see  The Medicinal Chemist’s Toolbox: An Analysis of Reactions Used in the Pursuit of Drug Candidates | Journal of Medicinal Chemistry ). That's an enormous percentage, given that the only more common classes are condensation, alkylation, and other Pd-catalyzed cross-coupling reactions are more common:   From Cooper, T. W. J.; Campbell, I. B.; Macdonald, S. J. F.,  Angew. Chem. Int. Ed....
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Liu loosens CO from renewable thiocarbonate platform

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 Citation:  Rajabimoghadam, K.; Faialaga, N.H.; Naito, N.; Li, Y.; Liu, R.Y. Photochemical CO Release from a Bench-Stable, Recyclable Organic Platform: Applications to Carbonylative Cross-Coupling.  Org. Lett.   2025 , ASAP.  Summary figure:   Background:  Carbonylation reactions are   really nice 3 component reactions that usually form ketones. I've posted about one of them previously (https://alwaysbecoupling.blogspot.com/2025/03/palladium-promotes-precise-conversions.html) if you want to see an example. The general idea is you can do migratory addition with a metal carbonyl to form a C-C bond, and then eventually reductively eliminate from the metal acyl complex to form another C-C bond.   Usually, there are two difficulties. First, you have to get the relative rates right, or else you can directly couple your R groups. This is also a common issue with other three-component coupling reactions like dicarbofunctionalizations.  Second, y...
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