886206-84-4Relevant academic research and scientific papers
Conformational Analysis of Acyclic α-Fluoro Sulfur Motifs
Erdeljac, Nathalie,Mück-Lichtenfeld, Christian,Daniliuc, Constantin G.,Gilmour, Ryan
, p. 13704 - 13715 (2020/10/02)
Bioactive small molecules containing α-fluoro sulfur motifs [RS(O)nCH2F] are appearing with increasing frequency in the pharmaceutical and agrochemical sectors. Prominent examples include the anti-asthma drug Flovent and t
Regiospecifically Fluorinated Polycyclic Aromatic Hydrocarbons via Julia-Kocienski Olefination and Oxidative Photocyclization. Effect of Fluorine Atom Substitution on Molecular Shape
Banerjee, Shaibal,Sinha, Saikat,Pradhan, Padmanava,Caruso, Alessio,Liebowitz, Daniel,Parrish, Damon,Rossi, Miriam,Zajc, Barbara
, p. 3983 - 3993 (2016/06/09)
A modular synthesis of regiospecifically fluorinated polycyclic aromatic hydrocarbons (PAHs) is described. 1,2-Diarylfluoroalkenes, synthesized via Julia-Kocienski olefination (70-99% yields), were converted to isomeric 5- and 6-fluorobenzo[c]phenanthrene, 5-and 6-fluorochrysene, and 9- and 10-benzo[g]chrysene (66-83% yields) by oxidative photocyclization. Photocyclization to 6-fluorochrysene proceeded more slowly than conversion of 1-styrylnaphthalene to chrysene. Higher fluoroalkene dilution led to a more rapid cyclization. Therefore, photocyclizations were performed at higher dilutions. To evaluate the effect of fluorine atom on molecular shapes, X-ray data for 5- and 6-fluorobenzo[c]phenanthrene, 6-fluorochrysene, 9- and 10-fluorobenzo[g]chrysene, and unfluorinated chrysene as well as benzo[g]chrysene were obtained and compared. The fluorine atom caused a small deviation from planarity in the chrysene series and decreased nonplanarity in the benzo[c]phenanthrene derivatives, but its influence was most pronounced in the benzo[g]chrysene series. A remarkable flattening of the molecule was observed in 9-fluorobenzo[g]chrysene, where the short 2.055 ? interatomic distance between bay-region F-9 and H-8, downfield shift of H-8, and a 26.1 Hz coupling between F-9 and C-8 indicate a possible F-9···H-8 hydrogen bond. In addition, in 9-fluorobenzo[g]chrysene, the stacking distance is short at 3.365 ? and there is an additional interaction between the C-11-H and C-10a of a nearby molecule that is almost perpendicular.
Expedient synthesis of α-substituted fluoroethenes
Mandal, Samir K.,Ghosh, Arun K.,Kumar, Rakesh,Zajc, Barbara
scheme or table, p. 3164 - 3167 (2012/06/04)
A mild and efficient synthesis of 1-aryl-1-fluoroethenes from benzothiazolyl (aryl)fluoromethyl sulfones and paraformaldehyde, under DBU- or Cs2CO3-mediated conditions at room temperature, is described. A comparable diethyl fluoro(naphthalen-2-yl)methylphosphonate reagent does not react with paraformaldehyde under these mild conditions. The utility of the methodology for synthesis of terminal α-fluoroalkenes bearing electron-withdrawing functionalities is also shown.
High-yield synthesis of fluorinated benzothiazolyl sulfones: General synthons for fluoro-Julia olefinations
Ghosh, Arun K.,Zajc, Barbara
, p. 1553 - 1556 (2007/10/03)
General, high-yield tandem electrophilic fluorination and modified Julia olefination for the synthesis of fluoro olefins is reported. A series of α-fluoro 1,3-benzothiazol-2-yl sulfone-based synthons were synthesized via deprotonation-fluorination. Of critical importance for high-yield fluorinations were heterogeneous reaction conditions, as under homogeneous conditions only starting sulfones were recovered. The α-fluoro 1,3-benzothiazol-2-yl sulfones so obtained were subjected to condensations with a variety of aldehydes and ketones to afford high yields of regiospecifically fluorinated olefins.
