Stereoselective formation of (Z)-2-fluoroalkenoates via Julia-Kocienski reaction of aldehydes with pyrimidinyl-fluoro-sulfones was written by Larnaud, Florent;Pfund, Emmanuel;Linclau, Bruno;Lequeux, Thierry. And the article was included in Tetrahedron in 2014.Name: 5-Nitrobenzothiazole-2-thiol This article mentions the following:
The selective synthesis of fluoroalkenoates is reported using a pyrimidine-fluoro-sulfone as a starting material. This sulfone allowed the preparation of (Z)-fluoroalkenoates with very high stereoselectivity from both aromatic and aliphatic aldehydes. The nature of the heterocycle on the course of the Julia-Kocienski reaction is discussed. A Julia-Kocienski reaction involves the formation of alkenes by a reaction of sulfones with aldehyde derivatives In this work the synthesis of the target compounds was achieved using 4-bromobenzaldehyde, 2,5-dibromobenzaldehyde, 2-thiophenecarboxaldehyde, 2-furancarboxaldehyde, heptanal, nonanal, 10-undecanal, (S)-citronellal, benzenepropanal, cyclohexanecarboxaldehyde, (1S,3R)-3-formyl-2,2-dimethylcyclopropanecarboxylic acid ester as aldehyde components. Sulfone components contained a fluorine group, such as 2-[(2-benzothiazolyl)sulfonyl]-2-(fluoro)acetic acid Et ester, 2-fluoro-2-[(2-pyridinyl)sulfonyl]acetic acid Et ester, 2-fluoro-2-[(2-pyrimidinyl)sulfonyl]acetic acid Et ester. The title compounds thus formed included (2Z)-3-(4-bromophenyl)-2-fluoro-2-propenoic acid ester, (2Z)-2-fluoro-3-(2-thienyl)-2-propenoic acid ester, (2Z)-2-fluoro-3-(2-furanyl)-2-propenoic acid ester, (2Z)-2-fluoro-2-nonenoic acid ester, (1S,3S)-3-[(1Z)-3-ethoxy-2-fluoro-3-oxo-1-propen-1-yl]-2,2-dimethylcyclopropanecarboxylic acid ester. In the experiment, the researchers used many compounds, for example, 5-Nitrobenzothiazole-2-thiol (cas: 58759-63-0Name: 5-Nitrobenzothiazole-2-thiol).
5-Nitrobenzothiazole-2-thiol (cas: 58759-63-0) belongs to thiazole derivatives. The thiazole ring is notable as a component of the vitamin thiamine (B1). The pyridine-type nitrogen in the thiazole ring deactivates the ring for electrophilic substitution reactions, which is further reduced in acid due to protonation of the thiazole ring.Name: 5-Nitrobenzothiazole-2-thiol
Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica