The Reaction of Sulfonylimido Intermediates With Aromatic Compounds

Abstract

'Therlnolysis of rnethanesulfonyl azide in aromatic solvents gives tnethanesulfonarnide and the isomeric niethanesulfonanilides. The orientation of the latter and the relative reactivities of the aromatic substrate towards attack by the ~nethylsulfonylimido intermediate have been studied quantitatively. The high reactivity and also great selectivity of the attacking species are interpreted in terms of a rate-determining addition process to give a sulfonylaziridine derivative followed by a product-deterlllining ring opening and rearrangement t o the substituted anilides. Partial rate factors are discussed, as are possible mechanisms for the formation of the rnethanesuifonamide. The ~netl~anesulfonylimido intermediate must be abstracting two hydrogen atoms synchronously from the aromatic substrate.

Metal-Catalyzed and Metal-Free Intermolecular Amination of Light Alkanes and Benzenes

“…30 Moreover, thermally-generated p -TolylSO 2 N nitrene adds to benzene twice as fast as it inserts into the C–H bonds of cyclohexane, whereas addition to p -xylene is 2.2 times faster than that of benzene. 29 These results, along with comparative rates of MeSO 2 N addition to substituted benzenes (anisole > toluene > benzene > chlorobenzene 2.54: 1.86: 1: 0.44; Scheme 3(d)), 31 are consistent with the highly electrophilic nature of the sulfonylimido active entities. Interestingly, the positional selectivity for MeSO 2 N attack on C 6 H 5 –X (X = MeO, Me, Cl; Scheme 3(d)) is highly favoring the ortho and para positions almost equivalently (very little meta products are observed), and cannot be fully rationalized by a typical homolytic (radical) aromatic substitution mechanism with an electrophilic radical.…”

Preparation and Properties of Imido Intermediates (Imidogens)

“…It is felt that this work needs careful quantitative re-examination before any conclusions concerning the mechanism of the reaction are reached. The thermal decomposition of methanesulfonyl azide in toluene indicates that the mesyl derivatives of 0-and p-toluidine are formed (with the former predominating) but that very little meta isomer is present (8). The reaction of benzenesulfonyl azide with a refluxing saturated solution of anthracene in chlorobenzene yielded a mixture of anthracene monosulfonamides together with comparable amounts of 0-and p-chlorobenzenesulfonamides.…”

Photochemistry of dibenzothiophene-based sulfilimines

“…The energy differences measured between the states have been determined spectroscopically. [15][16][17][18][19][20] Depending on the nature of the R group replacing the hydrogen atom, the degeneracy of the 1 Δ components can be lifted making either the 1 A' or the 1 A" the lowest singlet states.…”

“…The photochemistry of dibenzothiophene-S-oxide (DBTO), which results in formation of dibenzothiophene, is well documented. [10][11][12][13][14][15][16] Numerous experiments support the formation of O( 3 P) as the major mechanism, though indirectly.…”

“…Despite the apparent triplet multiplicity of the sulfonylnitrene ground states, thermolysis or photolysis of sulfonylazides generally leads to negligible amounts of triplet-nitrene-derived products. 7,[9][10][11][12][13][14][15] Complexities deriving from the possibility of reactions of the excited states of the azide (as opposed to going through the nitrene and from the hazards associated with smaller azides (e.g., mesyl azide) have been noted. 10,14,[16][17][18][19] Finally, SO 2 extrusion is observed under some circumstances.…”