121287-02-3Relevant academic research and scientific papers
KINETIC RESOLUTION OF EPOXIDES BY CHIRAL ORGANOALUMINIUM CALTALYST SHORT SYNTHESIS OF (-)-C16 JUVENILE HORMONE
Naruse, Yuji,Esaki, Toru,Yamamoto,Hisashi
, p. 4747 - 4756 (1988)
The use of chiral organoaluminium reagent as a catalyst to resolve simple ketoepoxides is explored.The optically pure ketoepoxide 10 was recovered after 80percent conversion.The recovered pure epoxides is a useful chiral building block in the synthesis of
N-(trifluoromethylsulfonyl)aryloxytrifluoromethylsulfoximines [ArO-SO(CF3)=NTf] and N-aryltriflimides Ar-N(Tf)2 by thermal and photolytic dediazoniation of [ArN2][BF4] in [BMIM][Tf2N] ionic liquid: Exploiting the ambident nucleophilic character of a "nonnucleophilic" anion
Laali, Kenneth K.,Okazaki, Takao,Bunge, Scott D.
, p. 6758 - 6762 (2008/02/10)
(Chemical Equation Presented) Arenediazonium tetrafluoroborate salts undergo metathesis on immobilization in 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonato)amide [BMIM][Tf2N]. The "noncoordinating", "nonnucleophilic" [Tf2N] anion acts as an ambident nucleophile toward the aryl cations, formed via thermal dediazoniation, to give predominantly the oxy anion quenching products [ArO-SO(CF3)=NTf], with minimal formation of ArN(Tf)2, irrespective of the nature of the substituent(s) on the ArN2 +. Strong preference for the formation of oxygen trapping products did not change under photolytic conditions, where dediazoniation occurs at room temperature. A minimal amount of the Schiemann product ArF is also formed in both thermal and photolytic dediazoniation, depending on the substituent(s). Progress of dediazoniation in the IL (both thermal and photolytic) and the evolution of the products were directly monitored by 1H and 19F NMR. According to DFT (Density Functional Theory) calculations, PhN(Tf)2 is more stable than PhO-SO(CF3)=NTf by 15-17 kcal/mol, depending on the basis set. Inclusion of solvation effects (PCM, with acetone and with CH2ClCH2Cl as solvent) did not change this preference. The [ArN2][BF4] dediazoniation in [BMIM][Tf2N] resulted in synthesis and characterization of a series of hitherto unknown [ArO-SO(CF3)=NTf] compounds. The X-ray structure of MesO-SO(CF3)=NTf (Mes = mesityl) is reported. On the basis of extraction studies, suitable solvent systems have been identified that remove the products without dissolving [BMIM][NTf2], thus overcoming product recovery difficulties typically associated with the use of this IL.
