In organic chemistry, umpolung (German: [ˈʔʊmˌpoːlʊŋ]) or polarity inversion is the chemical modification of a functional group with the aim of the reversal...

forget about their language and their origin. As a neologism, it echoes Umpolung, 'polarity inversion', leading to an interpretation akin to "ethnicity...

The Corey–Seebach reaction, or Seebach Umpolung is a name reaction of organic chemistry that allows for acylation by converting aldehydes into lithiated...

inversion of polarity between R'(H)Cδ+=Oδ− and R'CLi(SR)2 is referred to as umpolung. The reaction is commonly performed using the 1,3-dithiane. The lithiated...

Boluda CJ, Juncá C, Soto E, de la Cruz D, Peña A (13 December 2019). "Umpolung in reactions catalyzed by thiamine pyrophosphate dependent enzymes". Ciencia...

chemistry since the 1980s. They are related to enolates, but represent an umpolung of their reactivity. Homoenolates can be formed with a variety of different...

chloride is used to remove dithiane groups attached to a carbonyl in an umpolung reaction. This reaction exploits the high affinity of Hg2+ for anionic...

Polarity inversion may refer to: Polarity inversion (chemistry) (aka Umpolung), in organic chemistry Polarity inversion (differential pairs), swapping...

Aldol addition Acyloin condensation Cannizzaro reaction Stetter reaction Umpolung Menon, Rajeev S.; Biju, Akkattu T.; Nair, Vijay (2016). "Recent advances...

chemistry and on the synthesis of beta-peptides. The development of the umpolung, a polarity inversion of the carbonyl group, with 1,3-propanedithiol together...

produce an acyl anion equivalent (see cyanohydrin or aldehyde-dithiane umpolung chemistry, as well as benzoin condensation). This anion attacks S1 of an...

of Hg(II) for thiolates. 1,3-Dithianes are more importantly employed in umpolung reactions, such as the Corey–Seebach reaction: 1,4-Dithiane is an organosulfur...

formaldehyde. The reactivity of this dithiane illustrates the concept of umpolung. Alkylation gives thioethers, e.g. 1,5-dithiacyclooctane. The unpleasant...

They represent a subclass of sulfides. The thioacetals are useful in "umpolung" of carbonyl groups. Thioacetals and thioketals can also be used to protect...

triazolium salts to be effective. The Stetter reaction is an example of umpolung chemistry, as the inherent polarity of the aldehyde is reversed by the...

reactivity in displacement and addition reactions. Dithianation introduced umpolung chemistry, now a key concept in organic synthesis. The formations of dithianes...

apparatus Meitnerium Mischmetall (lit. "mixed metal"), alloy Roentgenium Umpolung (organic chemistry) Wolfram Zwitterion Allumwandlung Blitz chess, from...

diazaphospholenes (scheme 3), the polarity of the P-H bond can be inverted (see: umpolung) and the resulting phosphine hydride can reduce a carbonyl group as in...

S.; Yatham V. R.; Neudörfl J.-M.; Schlörer N. E.; Teles J. H. (2012). "Umpolung by N-Heterocyclic Carbenes: Generation and Reactivity of the Elusive 2...

Taylor, Carol M. (2006-08-01). "β-Glycosides of Hydroxyproline via an Umpolung Approach". Organic Letters. 8 (18): 3959–3962. doi:10.1021/ol061424m. ISSN 1523-7060...

resulting anion can be C-alkylated. The process is the foundation of the umpolung phenomenon. Like 1,2-ethanedithiol, propanedithiol forms complexes with...

(NHCs) are an emerging class of organocatalysts that are able to induce Umpolung reactivity as well as normal polarity transformations, however until recently...

S2CID 11653420. Dai, Xijie; Li, Chenchen; Li, Chao-Jun (April 2021). "Carbonyl umpolung as organometallic reagent surrogates". Chemical Society Reviews. 50 (19):...

PMID 15543313. Streuff, Jan (2011). "A titanium(III)-catalyzed redox Umpolung reaction for the reductive cross-coupling of enones with acrylonitriles"...

W.; Shevchenko, Nikolay; Alabugin, Igor V. (2013). ""Stereoelectronic Umpolung": Converting a p-Donor into a σ-Acceptor via Electron Injection and a Conformational...

intermediates may also intercept nucleophiles in a process that involves umpolung at the α carbon. In addition, because reduction of monohalo ketones produces...

doi:10.1038/nchem.1607. Xavier Bugaut, Frank Glorius: Organocatalytic umpolung: N-heterocyclic carbenes and beyond. In: Chemical Society Reviews. 41,...

diastereoselective β-lactam synthesis. Unlike the Staudinger β-lactam synthesis, the umpolung ketene in the Lectka β-lactam synthesis behaves as the nucleophile rather...

formation of the other allylic analog by logic similar to cyanide-type umpolung. It then later provides a good leaving group for formation of the iminium...