Synthesis and Reaction of α‐Dithiolactone

Abstract

Treatment of di-tert-butylthioketene S-oxide (5 a) with Lawesson reagent at room temperature resulted in the formation of 3,3-di-tert-butylthiirane-2-thione (4 a) in high yield. The oxidation of 4 a with mCPBA (mCPBA=m-chloroperbenzioc acid) gave 3,3-di-tert-butylthiirane-2-thione S-oxide (6) almost quantitatively. The reactions of 4 a with dimethyl acetylenedicarboxylate (DMAD) and benzyne afforded dimethyl 2-(2,2,4,4-tetramethylpentan-3-ylidene)-1,3-dithiole-4,5-dicarboxylate (13) and 2-(2,2,4,4-tetramethylpentan-3-ylidene)benzo[d][1,3]dithiole (15), respectively, in high yields, suggesting that 4 a is an excellent 1,3-dipole. The reaction of 4 a with ethylenebis(triphenylphosphine)platinum (16) gave dithiolato-platinum complex (22) in high yield. The structure of 22 was determined by X-ray crystallographic analysis.

o-Silylaryl Triflates: A Journey of Kobayashi Aryne Precursors

“…In Larock’s early study on O-nucleophilic annulation protocol, they also showed examples with respect to S-nucleophiles (Scheme a). , In 2006, Okuma et al. investigated the reactivity of 3,3-di- tert -butylthiirane-2-thione ( 6-77 ) with Kobayashi benzyne precursor and obtained an annulation product 2-(2,2,4,4-tetramethylpentan-3-ylidene)­benzo­[ d ]­[1,3]­dithiole ( 6-78 ) in 90% yield via intermediate 6-79 (Scheme a) . Subsequently, the same group examined the chemical behavior of 5-isopropylidene-4,4-dimehtyl-1,2-dithiolane-3-thione ( 6-80 ) and found that this compound could react with benzyne to generate benzo-1,3-dithiole 6-81 in 85% yield, the mechanistic pathway of which experiences the formation and recombination of a betaine intermediate 6-82 (Scheme b) …”

“…436,437 In 2006, Okuma et al investigated the reactivity of 3,3-di-tert-butylthiirane-2-thione (6-77) with Kobayashi benzyne precursor and obtained an annulation product 2-(2,2,4,4-tetramethylpentan-3-ylidene)benzo[d]- [1,3]dithiole in 90% yield via intermediate 6-79 (Scheme 86a). 472 Subsequently, the same group examined the chemical behavior of 5-isopropylidene-4,4-dimehtyl-1,2dithiolane-3-thione (6-80) and found that this compound could react with benzyne to generate benzo-1,3-dithiole 6-81 in 85% yield, the mechanistic pathway of which experiences the formation and recombination of a betaine intermediate 6-82 (Scheme 86b). 473 In 2015, Werz and co-workers prepared a series of amphiphilic benzodithioloimines 6-83 containing both positively and negatively polarized sulfur (Scheme 87).…”

ChemInform Abstract: The Topotactic Reduction of Sr3Fe2O5Cl2—Square Planar Fe(II) in an Extended Oxyhalide.

“…6 They demonstrated that these compounds were highly reactive towards [Pt 0 (PPh 3 ) 2 (η 2 ‐C 2 H 4 )] ( 5 ) and they characterized the isolated dithiolato complexes, as well as thiolato–sulfenato complexes, by X‐ray diffraction 6a. 7a–c A similar reactivity was observed for naphtha‐[1,8 cd ][1,2]dithiols towards Pt 0 –olefin complexes 7d. e Thus, Pt 0 –olefin complexes can be considered as suitable trapping agents for dithiiranes.…”

Parent Thioketene S‐Oxide H2CCSO: Gas‐Phase Generation, Structure, and Bonding Analysis

“…[5] In contrast, the knowledge about a,b-unsaturated sulfines R 2 C=C=S=O, also known as thioketene S-oxides, is limited, despite that their applicationsi nt he construction of three-membered cyclic a-dithiolactones have been reported. [6] Due to facile polymerization at room temperatures, only very few sterically stabilized thioketene S-oxides have been characterized, including the most frequently used di-tert-butylthioketene Soxide, which was synthesized from the oxidation of thioketene. [7] The simplest a,b-unsaturated sulfine H 2 C=C=S=O, which may also be considereda sv inylidene sulfoxide, remained elusive so far.A na ttempted synthesis from the flash vacuum pyrolysis (FVP) of two retro Diels-Alder precursors ethanoanthracenic sulfine and sulfoxide wasr eported by VallØee tal.…”