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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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