A relationship between the catalytic carbonylation of (N-arenesulfonyl)imides and iodonium ylides

Reactivities of various sulfonamide derivatives of general formula ArSO2N=X Phn (X = I; n = 1; X = S, Se, n = 2; X = P, As, n = 3) in catalytic carbony lations have been explained by structural properties of the substrates. Bas ed on crystallographic data reported in the literature, it has been conclud ed that the two-step catalytic oxidative carbonylation of sulfonylimides pr oceeds only when the N=X double bond is strongly polarized. The structural requirement observed within the sulfonamide derivatives has been found to b e applicable for iodonium ylides. Catalytic carbonylation of the phenyliodo nium methylide (3a) prepared from dimedone (5,5-dimethyl-1,3-cyclohexanedio ne) and (diacetoxyiodo)benzene, resulted in a new spirobenzofuranone deriva tive (5a) which was characterized by X-ray single crystal diffraction, (1)J (C,C) coupling constants, C-13-T-1 relaxation times, as well as by IR and R aman spectroscopic methods. Crystals of 5a are monoclinic, space group P2(1 )/c, a = 7.187(1), b = 21.129(1), and c = 10.636(1) Angstrom, beta = 92.81( 1)degrees, V = 1613.2(3) Angstrom (3), and Z = 4. A ketene intermediate has been postulated in the catalytic carbonylation of the iodonium ylide. A su rvey of databases has revealed that the triacyl dihydrofuranone moiety in 5 a constitutes a new structural unit.