Synthesis of SF5-substituted isoxazolidines using 1,3-dipolar cycloaddition reactions of nitrones with pentafluorosulfanyl acrylic esters and amides

Photoinitiated anti-Hydropentafluorosulfanylation of Terminal Alkynes

A photoinitiated anti-hydropentafluorosulfanylation of terminal alkynes using SF₅ Cl and (TMS)₃ SiH as the hydrogen atom donor is reported. This transformation generates selectively (Z)-(1-alken-1-yl)pentafluoro-λ⁶ -sulfanes (Z:E : >85:15), thus allowing the preparation of this previously unknown geometrical isomer. DFT calculations highlight that the selectivity is due to the intrinsic preference of SF₅ -substituted vinylic radicals to adopt a cis geometry, and to increased steric contacts during the transition structures leading to the minor (E)-products.

Crystal structure of (2R*,3aR*)-2-phenylsulfonyl-2,3,3a,4,5,6-hexahydropyrrolo[1,2-b]isoxazole

A new isoxazolidine has been obtained by 1,3-dipolar cyclo­addition of a nitrone and phenyl vinyl sulfone

The title compound, C₁₂H₁₅NO₃S, was prepared by 1,3-dipolar cyclo­addition of 3,4-di­hydro-2H-pyrrole 1-oxide and phenyl vinyl sulfone. In the mol­ecule, both fused five-membered rings display a twisted conformation. In the crystal, C—H⋯O hydrogen bonds link neighbouring mol­ecules, forming chains running parallel to the b axis.

Regio- and stereoselective synthesis of novel isoxazolidine heterocycles by 1,3-dipolar cycloaddition between C-phenyl-N-methylnitrone and substituted alkenes. Experimental and DFT investigation of selectivity and mechanism

A series of isoxazolidine heterocycles was synthesized through the 1,3-dipolar cycloaddition (13DC) reaction of C-phenyl-N-methylnitrone with different substituted alkenes.

SF5-Enolates in Ti(IV)-Mediated Aldol Reactions

The F···Ti bonding in the transition structures determines high trans- and syn-diastereoselectivities for aldol reactions of SF5-acetates with aldehydes in the presence of TiCl4 in the non-nucleophilic solvent CH2Cl2. Such bonding is canceled in nucleophilic solvents where opposite cis-stereochemistry is observed. The potential of thus obtained stereoisomeric SF5-aryl acrylates as dipolarophiles in the preparation of SF5-containing heterocycles is demonstrated.

G, Malik A, Kumar V, Chatterjee A, Roy BG, Banerjee M. In situ mechanochemical synthesis of nitrones followed by 1,3-dipolar cycloaddition: a catalyst-free, “green” route to cis-fused chromano[4,3-c]isoxazoles

An efficient, catalyst free mechanochemical route to cis-fused chromano[4,3-c]isoxazoles has been developed via a simple mortar-pestle grinding method.