Thiophenol-Azobisisobutyronitrile

Solubility sol acetonitrile, benzene, carbon tetrachloride, dichlo-romethane, toluene insol hexane. 

Preparative Method prepared by reaction of phosphoms(V) sulfide with vinylene carbonate.  

PuriScation recrystallization from benzene-hexane gives white crystals sublimation at 120 °C generates long white needles. Handling, Storage, and Precaution material is apparently stable. 

Cyclization with Dienes. The reaction of 2-thiono-l,3-dioxol-4-ene with anthracene at elevated temperatures leads to the production of the bicyclic adduct (1) (eq 1). No other dienes have been reported to cyclize with this reagent. Diels-Alder adducts could be treated with phosphines to effect a Corey-Winter aUcenation, which would render the reagent an acetylene equivalent. 

Synthesis of Ketene. Photolysis (270 nm) of 2-thiono-l,3-dioxol-4-ene results in the quantitative formation of ketene via Wolff rearrangement of the corresponding a-ketocarbenes (eq 2). Substituted dioxolenes can also be used in this fashion to generate substituted ketenes (eq 3). This serves as a convenient alternative to the use of a-diazo ketones in the generation of ketenes. 

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Konig et al. have achieved thioether functionalization of T8[CH = CH2]8 via the radical addition of thiols such as thiophenol, cyclohexylthiol, and 2-mercaptopyridine in the presence of azobisisobutyronitrile (AIBN) as a radical initiator (Table 13), while Gao et al. have also used this method to prepare very highly functionalized POSS by reacting T8[CH = CH2]8 with thiol-terminated glycosides giving glycoclusters in 70% yield (Figure 22). 

The catalytic activity of cinchonidine, cinchonine, quinine and quinidine, bonded to crosslinked polystyrene bearing thiole residues in the presence of azobisisobutyronitrile, as exemplified in Scheme 3.18, was compared in the enantioselective addition of thiophenols to 2-cyclohexen-l-one (Scheme 3.19). ... 

That a typical free radical initiator, azobisisobutyronitrile, would also catalyze this process was demonstrated by Walling and Rabinowitz (299,300), who proposed direct reaction of thiyl radicals on phosphite to yield an intermediate phosphoranyl radical identical to that produced in the homolytic reaction of disulfides with phosphites. For thiophenol and triethyl phosphite, an ionic reaction to produce phenyl ethyl sulfide and diethyl phosphite is favored even in the presence of di- cr butyl peroxide (298). 

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