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1. Relative hydrophilicities of cis and trans formamides

   https://doi.org/10.1073/pnas.1911331116  

   Li, Yong-Sheng; Escobar, Luis; Zhu, Yu-Jie; Cohen, Yoram; Ballester, Pablo; Rebek, Julius; Yu, Yang (October 2019, Proceedings of the National Academy of Sciences)

   Secondary formamides are widely encountered in biology and exist as mixtures of both cis and trans isomers. Here, we assess hydrophilicity differences between isomeric formamides through direct competition experiments. Formamides bearing long aliphatic chains were sequestered in a water-soluble molecular container having a hydrophobic cavity with an end open to the aqueous medium. NMR spectroscopic experiments reveal a modest preference (<1 kcal/mol) for aqueous solvation of the trans formamide terminals over the cis isomers. With diformamides, the supramolecular approach allows staging of intramolecular competition between short-lived species with subtle differences in hydrophobic properties. 

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2. Technical note: Improved synthetic routes to cis - and trans -(2-methyloxirane-2,3-diyl)dimethanol ( cis - and trans - β -isoprene epoxydiol)

   https://doi.org/10.5194/acp-23-7859-2023  

   Frauenheim, Molly; Surratt, Jason D.; Zhang, Zhenfa; Gold, Avram (July 2023, Atmospheric Chemistry and Physics)

   Abstract. We report improved synthetic routes to the isomericisoprene-derived β-epoxydiols (β-IEPOX) in high yield(57 %–69 %) from inexpensive, readily available starting compounds. Thesyntheses do not require the protection/deprotection steps or time-consumingpurification of intermediates and can readily be scaled up to yield thetarget IEPOX isomers in gram quantities. Emissions of isoprene(2-methyl-1,3-butadiene, C5H8), primarily from deciduousvegetation, constitute the largest source of nonmethane atmospherichydrocarbons. In the gas phase under low-nitric-oxide (NO) conditions,addition of the atmospheric hydroxyl radical (OH) followed by rapid addition ofO2 yields isoprene-derived hydroxyperoxyl radicals. The major sink(>90 %) for the peroxyl radicals is a sequential reaction withthe hydroperoxyl radical (HO2), OH, and O2, which is then followed bythe elimination of OH to yield a ∼2:1 mixture ofcis- and trans-(2-methyloxirane-2,3-diyl)dimethanol (cis- and trans-β-IEPOX). The IEPOXisomers account for about 80 % of closed-shell hydroxyperoxylproducts and are rapidly taken up into acidic aerosols to form secondaryorganic aerosol (SOA). IEPOX-derived SOA makes a significant masscontribution to fine particulate matter (PM2.5), which is known to be amajor factor in climate forcing as well as adversely affecting respiratory andcardiovascular systems of exposed populations. Prediction of ambientPM2.5 composition and distribution, both in regional- and global-scaleatmospheric chemistry models, crucially depends on the accuracy ofidentification and quantitation of uptake product formation. Accessibilityof authentic cis- and trans-β-IEPOX in high purity and in large quantity forlaboratory studies underpins progress in developing models as well asidentification and quantitation of PM2.5 components. 

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3. Electronic Spectroscopy of cis - and trans - meta -Vinylbenzyl Radicals

   https://doi.org/10.1021/acs.jpca.1c04496  

   Ross, Sederra D.; Flores, Jonathan; Hewett, Daniel M.; Reilly, Neil J. (July 2021, The Journal of Physical Chemistry A)
4. Spectral analyses of trans - and cis -DOCO transients via comb spectroscopy

   https://doi.org/10.1080/00268976.2018.1484949  

   Bui, Thinh Q.; Changala, P. Bryan; Bjork, Bryce J.; Yu, Qi; Wang, Yimin; Stanton, John F.; Bowman, Joel; Ye, Jun (May 2018, Molecular Physics)
5. Linear and Nonlinear Optical Properties of All- cis and All- trans Poly( p -phenylenevinylene)

   https://doi.org/10.1021/acs.jpcc.3c07082  

   Mandal, Haraprasad; Ogunyemi, Olusayo J.; Nicholson, Jake L.; Orr, Meghan E.; Lalisse, Remy F.; Rentería-Gómez, Ángel; Gogoi, Achyut R.; Gutierrez, Osvaldo; Michaudel, Quentin; Goodson, III, Theodore (February 2024, The Journal of Physical Chemistry C)