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28 Aug 11:46

[ASAP] Extraction of Natural Pigments from Mediterranean Flowers and Fruits: A Sustainable Approach to Plant-Based Colorants

by Jorge Jordán-Núñez, Iria Costa-Torrado, Marta Pérez-Cabezas, Antonio Belda, Macarena Boix, and Bàrbara Micó-Vicent

TOC Graphic

ACS Sustainable Chemistry & Engineering
DOI: 10.1021/acssuschemeng.5c03477
15 Aug 08:45

[ASAP] Electrolysis for Valorization of Industrially-Sourced Crude Glycerol

by Rachel N. Gaines, Adam P. Sibal, Abiela M. Bradley, James J. Griebler, Vijay M. Shah, Bridget E. Friel, Simon A. Rogers, Ashlynn S. Stillwell, and Paul J. A. Kenis

TOC Graphic

ACS Sustainable Chemistry & Engineering
DOI: 10.1021/acssuschemeng.5c03028
14 Aug 13:05

Direct electrochemical deoxygenation reaction of ketones using leaded bronze cathode in formic acid

Green Chem., 2025, 27,10801-10807
DOI: 10.1039/D5GC03495G, Paper
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Sebastian Kissel, Marcel Nicolas Perner, Rok Narobe, Kyra Hochadel, Martin Klein, Bertram Cezanne, Philipp Schnieders, Volker Derdau, Siegfried R. Waldvogel
A mild, resource efficient electrochemical deoxygenation reaction of ketones with a reusable leaded bronze cathode and recyclable electrolyte is reported. Simple workup by phase separation provides pre-requisites for potential technical applications.
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02 May 15:13

[ASAP] Nickel/Photoredox Dual-Catalyzed, Regioselective 1,2-Carboacylation of Alkenes via Synergistic Alkyl and Benzoyl Radical Coupling

by Xian-Chen He, Jie Gao, Li Yang, Kai Chen, and Hua Yang

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Organic Letters
DOI: 10.1021/acs.orglett.5c01230
02 May 14:52

Star Ownership

by xkcd

If every country's airspace extended up forever, which country would own the largest percentage of the galaxy at any given time?

Reuven Lazarus

Today's question is adapted from What If 2: Additional Serious Scientific Answers to Absurd Hypothetical Questions, which contains many more What If answers and is available now!

Congratulations to Australia, new rulers of the galaxy.

The Australian flag has a number of symbols on it, including five stars that represent the stars of the Southern Cross.[1] Based on the answer to this question, maybe their flag designers should think bigger.

Countries in the southern hemisphere have an advantage when it comes to star ownership. Earth's axis is tilted relative to the Milky Way; our North Pole points generally away from the galaxy's center.

If each country's airspace extended upward forever, the core of the galaxy would stay under the control of countries in the southern hemisphere, changing hands over the course of each day as the Earth rotates.

At its peak, Australia would control more stars than any other country. The supermassive black hole at the core of the galaxy would enter Australian airspace every day south of Brisbane, near the small town of Broadwater.

After about an hour, almost the entire galactic core—along with a substantial chunk of the disk—would be within Australian jurisdiction.

At various times throughout the day, the galactic core would pass through the domain of South Africa, Lesotho, Brazil, Argentina, and Chile. The United States, Europe, and most of Asia would have to be content with outer sections of the galactic disk.

The northern hemisphere isn't left with the dregs, though. The outer galactic disk has some cool things in it—like Cygnus X-1, a black hole currently devouring a supergiant star.[2] Each day, as the core of the galaxy crossed the Pacific, Cygnus X-1 would enter the United States's airspace over North Carolina.

While owning a black hole would be cool, the United States would also have millions of planetary systems constantly moving in and out of its territory—which might cause some problems.

The star 47 Ursae Majoris has at least three planets and probably more. If any of those planets have life on them, then once a day all that life passes through the United States. That means that there's a period of a few minutes each day where any murders on those planets technically happen in New Jersey.

Luckily for the New Jersey court system, altitudes above about 12 miles are generally considered "high seas." According to the American Bar Association's Winter 2012 issue of the Admiralty and Maritime Law Committee Newsletter, this means that deaths above these altitudes—even deaths in space—are arguably covered by the 1920 Death on the High Seas Act, or DOHSA.

But if any aliens on 47 Ursae Majoris are considering bringing a lawsuit in a US court under DOHSA, they're going to be disappointed. DOHSA has a statute of limitations of 3 years, but 47 Ursae Majoris is more than 40 light-years away...

...which means it's physically impossible for them to file charges in time.

[1] Epsilon Crucis has five points, while the others have seven, implying that the view of Epsilon is from a telescope with different lens geometry from the others. Minor symbolic/graphic design choice? Or clue to a secret multiversal alliance between parallel universe Australias? No way to know for sure!

[2] Cygnus X-1 was the subject of a famous bet between astrophysicists Stephen Hawking and Kip Thorne over whether it was a black hole or not. Hawking, who had spent much of his career studying black holes, bet that it wasn't. He figured that if black holes turned out not to exist, at least he would win the bet as a consolation prize. In the end, luckily for his legacy, he lost.

06 Dec 12:28

[ASAP] Biocatalytically Generated Library of Chiral Building Blocks Containing a Quaternary Stereocenter

by Emina Mehić, Robert Junior Kolman, Irena Dokli, and Maja Majerić Elenkov

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Organic Letters
DOI: 10.1021/acs.orglett.4c03399
23 Sep 10:51

Dynamic Asymmetric Diamination of Allylic Alcohols through Borrowing Hydrogen Catalysis: Diastereo‐Divergent Synthesis of Tetrahydrobenzodiazepines

by Yufeng Liu, Peng Ji, Gongfeng Zou, Yongbing Liu, Bin-Miao Yang, Yu Zhao
Dynamic Asymmetric Diamination of Allylic Alcohols through Borrowing Hydrogen Catalysis: Diastereo-Divergent Synthesis of Tetrahydrobenzodiazepines

We present herein an unprecedented, catalytic enantioconvergent diamination of racemic allylic alcohols with the construction of two C−N bonds and 1,3-nonadjacent stereocenters. This iridium/chiral phosphoric acid cooperative catalytic system operates through an atom-economical borrowing hydrogen amination/aza-Michael cascade, and converts readily available phenylenediamines and racemic allylic alcohols to 1,5-tetrahydrobenzodiazepines in high enantioselectivity. An intriguing solvent-dependent switch of diastereoselectivity was also observed.


Abstract

We present herein a catalytic enantioconvergent diamination of racemic allylic alcohols with the construction of two C−N bonds and 1,3-nonadjacent stereocenters. This iridium/chiral phosphoric acid cooperative catalytic system operates through an atom-economical borrowing hydrogen amination/aza-Michael cascade, and converts readily available phenylenediamines and racemic allylic alcohols to 1,5-tetrahydrobenzodiazepines in high enantioselectivity. An intriguing solvent-dependent switch of diastereoselectivity was also observed. Mechanistic studies suggested a dynamic kinetic resolution process involving racemization through a reversible Michael addition, making the last step of asymmetric imine reduction the enantiodetermining step of this cascade process.

17 Sep 12:46

Harnessing the versatility of hydrazones through electrosynthetic oxidative transformations

by Aurélie Claraz

Abstract

Hydrazones are important structural motifs in organic synthesis, providing a useful molecular platform for the construction of valuable compounds. Electrooxidative transformations of hydrazones constitute an attractive opportunity to take advantage of the versatility of these reagents. By directly harnessing the electrical current to perform the oxidative process, a large panel of organic molecules can be accessed from readily available hydrazones under mild, safe and oxidant-free reaction conditions. This review presents a comprehensive overview of oxidative electrosynthetic transformations of hydrazones. It includes the construction of azacycles, the C(sp2)−H functionalization of aldehyde-derived hydrazones and the access to diazo compounds as either synthetic intermediates or products. A special attention is paid to the reaction mechanism with the aim to encourage further development in this field.

Beilstein J. Org. Chem. 2024, 20, 1988–2004. doi:10.3762/bjoc.20.175

17 Sep 12:44

Deuterated reagents in multicomponent reactions to afford deuterium-labeled products

by Kevin Schofield, Shayna Maddern, Yueteng Zhang, Grace E. Mastin, Rachel Knight, Wei Wang, James Galligan and Christopher Hulme

Abstract

The utility of bio-isosteres is broad in drug discovery and methodology herein enables the preparation of deuterium-labeled products is the most fundamental of known bio-isosteric replacements. As such we report the use of both [D1]-aldehydes and [D2]-isonitriles across 8 multicomponent reactions (MCRs) to give diverse arrays of deuterated products. A highlight is the synthesis of several FDA-approved calcium channel blockers, selectively deuterated at a t1/2 limiting metabolic soft-spot via use of [D1]-aldehydes. Surrogate pharmacokinetic analyses of microsomal stability confirm prolongation of t1/2 of the new deuterated analogs. We also report the first preparation of [D2]-isonitriles from [D3]-formamides via a modified Leuckart–Wallach reaction and their use in an MCR to afford products with [D2]-benzylic positions and likely significantly enhanced metabolic stability, a key parameter for property-based design efforts.

Beilstein J. Org. Chem. 2024, 20, 2270–2279. doi:10.3762/bjoc.20.195

17 Sep 12:37

Practical electrochemical hydrogenation of nitriles at the nickel foam cathode

Green Chem., 2024, 26,10567-10574
DOI: 10.1039/D4GC03446E, Paper
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Rok Narobe, Marcel Nicolas Perner, María de Jesús Gálvez-Vázquez, Conrad Kuhwald, Martin Klein, Peter Broekmann, Sina Rösler, Bertram Cezanne, Siegfried R. Waldvogel
We report a scalable hydrogenation method for nitriles based on cost-effective materials in a very simple two-electrode setup under galvanostatic conditions.
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