Synthesis and photochromism of some mono and bis (thienyl) substituted oxathiine 2,2-dioxides

Abstract

The addition of sulfenes to substituted enaminoketones, followed by a facile Cope elimination, provides access to a novel series of photochromic dithienylethenes containing a 1,2-oxathiine 2,2-dioxide core.

Synthesis, C–H bond functionalisation and cycloadditions of 6-styryl-1,2-oxathiine 2,2-dioxides

“…Unless otherwise stated, reagents and solvents were purchased from major chemical catalogue companies and were used as supplied. Routine 1 H NMR (400 MHz) and 13 C NMR (100 MHz) spectra were recorded on a Bruker Avance DPX400 in CDCl 3 . Occasional 1 H NMR spectra were also recorded on a Bruker Avance 300 MHz instrument in CDCl 3 .…”

“…Physical and spectroscopic data were identical to previously prepared material. 13 3-(4-Methoxyphenyl)-5,6-diphenyl-1,2-oxathiine 2,2-dioxide 6b. 5,6-Diphenyl-1,2-oxathiine 2,2-dioxide (0.20 g, 0.7 mmol, 1.0 eq.…”

“…9,10 Recently, the 1,2oxathiine 2,2-dioxide unit has attracted interest in materials application including in energy storage/battery technology, 11 as photoresists for high resolution lithography 12 and as a core unit in a photochromic dithienylethene. 13 The synthesis, chemistry and applications of 1,2-oxathiine 2,2-dioxides has recently been reviewed. 14 We have previously reinvestigated the relatively scarcely employed addition of sulfenes to enaminoketones [15][16][17][18] as a route to diversely substituted 4-dialkylamino-3,4-dihydro-1,2-oxathiine 2,2-dioxides and successfully eliminated the dialkylamine moiety to afford a series of unsaturated mono-, di-and tri-(hetero)aryl substituted 1,2-oxathiine 2,2-dioxides (Scheme 1).…”

“…14 We have previously reinvestigated the relatively scarcely employed addition of sulfenes to enaminoketones [15][16][17][18] as a route to diversely substituted 4-dialkylamino-3,4-dihydro-1,2-oxathiine 2,2-dioxides and successfully eliminated the dialkylamine moiety to afford a series of unsaturated mono-, di-and tri-(hetero)aryl substituted 1,2-oxathiine 2,2-dioxides (Scheme 1). 13,19 In this work we explore the selectivity of the addition of sulfenes to α,β-unsaturated enaminoketones derived from either (E)-4-arylbut-3-en-2-ones or 4-phenylbut-3-yn-2-one to afford unsaturated 1,2-oxathiine 2,2-dioxides bearing either a C-6 arylethenyl or arylethynyl moiety after Cope elimination of the amine function from the intermediate 3,4-dihydro 1,2oxathiine 2,2-dioxides. Further functionalisation of the oxathiine dioxide ring is examined by transition metalmediated cross-coupling and cycloaddition chemistry leading to diversely substituted derivatives.…”

Expedient synthesis of highly substituted 3,4-dihydro-1,2-oxathiine 2,2-dioxides and 1,2-oxathiine 2,2-dioxides: revisiting sulfene additions to enaminoketones

“…26 We have previously examined the synthesis of a novel dithienylethene photochromic system in which the ethene bridge forms part of a 1,2-oxathiine 2,2-dioxide ring. 27 In the latter work the…”