The Regiochemistry of Cyclization of α-Sulfenyl-, α-Sulfinyl-, and α-Sulfonyl-5-hexenyl Radicals:  Procedures Leading to Regioselective Syntheses of Cyclic Sulfones and Sulfoxides

Della, Ernest W.; Graney, Sean D.

doi:10.1021/jo0497306

Cited by 21 publications

(22 citation statements)

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“…The resulting triester was hydrolyzed and decarboxylated yielding dicarboxylic acid 29 as a mixture of diastereoisomers . Anhydride formation and basic equilibration furnished cis ‐dimethyl‐substituted substrate 30 , which was reduced with lithium aluminium hydride to yield diol 31 , activated, and reacted with sodium sulfide to thiane derivative 1 .…”

Section: Resultsmentioning

confidence: 99%

“…Ozonolysis with oxidative workup furnished a dicarboxylic acid. Esterification to 34 and reduction gave the diol 35 (R = t Bu) which was again activated and reacted with sodium sulfide to yield the tert ‐butyl‐substituted thiane 9 .…”

Section: Resultsmentioning

confidence: 99%

“…The unsymmetrical nature of 2,4‐dimethylthiane ( 17 ) and its derivatives prevented a comparably simple synthetic approach. 4‐Methylthiane ( 36 ) is accessible from diol 35 (R = Me) by the proven activation and reaction with sodium sulfide (Scheme ) . Oxidation with potassium permanganate furnished the respective sulfone 37 , which could be deprotonated with butyllithium and methylated with methyl iodide.…”

Section: Resultsmentioning

confidence: 99%

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Stereoelectronic Effects: Perlin Effects in Thiane‐Derived Compounds

et al. 2020

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Stereoelectronic effects in thianes and thiane-derived sulfoxides, sulfones, sulfilimines, and sulfoximines were investigated by measuring 1 J C,H coupling constants and by identification of normal and reversed Perlin effects, i.e., of differences in the coupling constants for equatorial and axial C-H bonds in the methylene groups of six-membered rings. The Perlin effects were correlated with results from natural bond orbital (NBO) [a] Compounds 1-19 were used for NMR spectroscopic investigations, where 2,4-dimethyl-substituted compounds 17-19 were investigated for comparison. Only the sulfide 17, the equatorial sulfoxide 18, and the respective sulfone 19 were synthesized with this substitution pattern. The parent compounds 20-27 were used for calculations. Scheme 2. Synthesis of thiane 9. a) PhCHO, KOH, EtOH/H 2 O (78 %); b) O 3 , AcOH, 10°C, 5 h, then H 2 O 2 , reflux, 3 h; c) EtOH, cat. H 2 SO 4 , PhMe; Dean-Stark trap, 16 h (46 %); d) LiAlH 4 , Et 2 O, r.t., 16 h (93 %); e) MsCl, Et 3 N, CH 2 Cl 2 , r.t., 1 h (99 %); f) Na 2 S, EtOH/H 2 O, reflux, 2 h (78 %).Functionalization of thianes 1 and 9 was achieved with proven methods (Scheme 3). Oxidation with ozone yielded the equatorial sulfoxides 2 and 10, respectively, with good yields. [14] The axial sulfoxides (3 and 11) were obtained with a known protocol [14] by oxidation with tert-butyl hypochloride, albeit with quite poor yields. Excellent yields were observed in the preparation of sulfones 4 and 12, which was achieved with Eur. 2879 Scheme 4. Synthesis of 2,4-dimethylthiane derivatives. Conditions: a) MsCl, Et 3 N, CH 2 Cl 2 , 0°C, 45 min (quant.); b) Na 2 S, MeOH/H 2 O, reflux, 2 h (65 %); c) KMnO 4 , CH 2 Cl 2 /H 2 O, r.t., 16 h (94 %); d) BuLi, THF, 0°C to r.t., 30 min, then MeI, 0°C to r.t. (19: 17 %, 18: 30 %, diastereomerically pure); e) O 3 , CH 2 Cl 2 , -40°C to r.t., 2 h (67 %, d.r. = 5.8:1); f) P 4 S 10 , CDCl 3 .

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

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Stereoelectronic Effects: Perlin Effects in Thiane‐Derived Compounds

et al. 2020

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“…Oxidation of thioether 1 to the corresponding sulfoxide was achieved using sodium metaperiodate in aqueous methanol. 40 Selective oxidation occurred and recrystallization of 3 gave a pure diastereomeric sulfoxide whose structure including stereochemistry was unequivocally established by an X-ray crystallographic structure study. An ORTEP drawing of this sulfoxide is shown in the Supplementary Material (Fig.…”

Section: Chemical Synthesis Ofmentioning

confidence: 97%

“…The method reported by Della and Graney for oxidizing thioethers to sulfoxides was slightly modified and used 40. Sodium metaperiodate (93.9 mg, 0.439 mmol) was slowly added to a solution of 6-endo-(methylthio)bicyclo[2.2.1]heptan-2-endo-pyrrolidine amide, 1 (100 mg, 0.418 mmol) in methanol/H 2 O (0.75 mL/0.75 mL) cooled in ice-water bath under Ar.…”

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Neighboring amide participation in the Fenton oxidation of a sulfide to sulfoxide, vinyl sulfide and ketone relevant to oxidation of methionine thioether side chains in peptides

et al. 2016

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Oxidation of Met affects the stability of proteins, and was identified as a step in the beta amyloid-dependent pathogenesis of Alzheimer's disease. One-electron oxidation of Met is facilitated through stabilization of sulfide radical cations with electron-rich heteroatoms. The formation of such 2-center-3-electron bonds, formed between sulfide radical cations and amides, leads to pronounced product selectivity during biologically relevant oxidation conditions. Conformationally constrained methionine analogs embedded within a norbornane framework, i.e., 2,6-endo, endo-and 2,6-exo, endo-pyrrolidine amide thiomethyl bicyclo[2.2.1]heptanes

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Advances in Free Radical Reactions of Organoselenium and Organotellurium Compounds

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Patai's Chemistry of Functional Groups

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Free radical reactions of organoselenium and tellurium compounds have been widely studied and exploited since the first two volumes of this series appeared. Alkyl aryl selenides and tellurides undergo alkyl C‐Se or C‐Te cleavage with stannanes or silanes to generate alkyl radicals that can be employed in reductions, allylations and both intermolecular and intramolecular additions to a large variety of unsaturated substrates, terminated by either hydrogen or arylchalcogen transfer. Selenoesters, telluroesters and related species generate acyl radicals that are useful in overall decarboxylations of carboxylic acids, and in addition and radical cyclization processes, including cascade reactions of polyenes to afford polycyclic products. Homolytic cleavage of diselenides and ditellurides produces selenyl and telluryl radicals that can be employed in additions to unsaturated acceptors, while the dichalcogenides themselves function as effective trapping agents for radicals produced in a variety of other ways, as from Barton thiohydroxamates. Selenols are efficient hydrogen donors that are of importance in kinetic studies of radical processes. When selenium and tellurium are joined to other heteroatoms, the resulting reagents effect radical 1,2‐additions to unsaturated substrates, as in the case of selenosulfonation and azidoselenenylation reactions. Other radical processes include oxidations, S H 2 substitutions, single electron transfers, extrusions and fragmentations, and reactions performed on solid supports. The synthetic utility of these processes, as well as mechanistic considerations are covered in this chapter.

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The Regiochemistry of Cyclization of α-Sulfenyl-, α-Sulfinyl-, and α-Sulfonyl-5-hexenyl Radicals: Procedures Leading to Regioselective Syntheses of Cyclic Sulfones and Sulfoxides

Cited by 21 publications

References 60 publications

Stereoelectronic Effects: Perlin Effects in Thiane‐Derived Compounds

Stereoelectronic Effects: Perlin Effects in Thiane‐Derived Compounds

Neighboring amide participation in the Fenton oxidation of a sulfide to sulfoxide, vinyl sulfide and ketone relevant to oxidation of methionine thioether side chains in peptides

Advances in Free Radical Reactions of Organoselenium and Organotellurium Compounds

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