Studies in mass spectrometry—XV

The halogenation of β-ketosulfones such as α-methylsulfonylacetophenone (1) and benzenesulfonylacetone (10) can be effected with sulfuryl chloride or pyridinium bromide perbromide. Regiochemical control can be achieved by control of stoichiometry and/or the reaction conditions. Detailed 1H and 13C nmr, and mass spectra are recorded for a series of halogenated β-ketosulfones, together with structures by X-ray crystallography for 1, 2-chloro-2-methylsulfonyl-1-phenylethanone (2), chloromethyl methyl sulfone (4), and α-chloroacetophenone (21). Results from these studies are used to suggest a reason for the difficulty associated with substitution reactions of α-halosulfones.

Section: Mass Spectrasupporting

confidence: 71%

Section: Preparations and Reactionsmentioning

confidence: 82%

The preparation, spectral properties, structures, and base-induced cleavage reactions of some α-halo-β-ketosulfones

Grossert¹,

Dubey²,

Gill³

et al. 1984

“…Methyl phenyl sulfone (1) has been studied before and our results agree with those of Bowie et al (2). The major fragmentation paths (Scheme 1) are reproduced here for c~m p a r i s o n .~ The spectrum4 of methyl benzenesulfinate (2)3 contains the molecular ion at m/e 156 and the loss of the methoxy group leads to the base peak at mle 125 (ion a in Scheme 1).…”

Section: Resultssupporting

confidence: 85%

“…The mass spectra of diary1 sulfones (1) and alkyl aryl sulfones (2) have been interpreted partly in terms of a rearrangement in which an aryl group migrates from sulfur to oxygen. In some cases there is evidence for the migration of alkyl groups (3).…”

Section: Introductionmentioning

confidence: 99%

Mass Spectra of Some Sulfinate Esters and Sulfones

Baarschers¹,

Krupay²

1973

“…Ring expansion of the 3,3-dimethyl sulfoxide 17, for example, to the cyclic sulfenate 23 has ample analogy in mass spectrometry (15) and might proceed in either a concerted or a stepwise fashion. Further photolysis of the sulfenate leading to the biradical 24, followed by desulfurization5 and (intramolecular) hydrogen transfer froin C-2 to the phenyl ring position vacated by sulfur, would lead t o the initially formed SAs one of the referees has pointed out, this step appears significantly endothermic, and is perhaps, therefore, the major weakness in this suggested mechanism.…”

Section: C6hscoohmentioning

confidence: 99%

Photochemical rearrangements of substituted thiochromanone sulfoxides

Still¹,

Arora²,

Chauhan³

et al. 1976

The photochemical behavior of a number of substituted derivatives of thiochroman-4-one 1-oxide has been examined. In contrast to the analogous sulfones these sulfoxides undergo a variety of photochemical rearrangements. At least three distinct pathways have been recognized; β-hydrogen abstraction or rearrangement to cyclic sulfenates, which then undergo further reaction by homolysis of the S—O bond, appearing to be particularly favorable processes. In a small number of examples, photochemical deoxygenation is observed as a competing reaction. Mechanisms which attempt to account for the influence of structural variations on the particular pathway followed have been proposed.