Thallium triacetate alkenes

Alkenes were reacted with thallium triacetate and azidotrimethylsilane to give 0-azidoalkyl thallium compounds, which were converted in situ to aziridinylazothallium compounds70,71. Only in the case of norbornene derivatives were the initial adducts (cxo.cw-azido-thallium compounds) isolated72. The aziridinylazothallium compound derived from cyclohexene 1 underwent thermal decomposition to give the trans-1,2-diazide, 2 in low yield. However, on treatment with acyl halides or trifluoroacetic anhydride, compound 1 afforded the corresponding 0-halo or 0-trifluoroacetoxy azides70. 

Thallium triacetate, TI(0C0CH3)3 1.5H20 (mp 182 C), like the monoacetate, is used for the stereoselective acetoxylation of alkenes [411] and for oxidations of alkenes to epoxides [412]. 

Acyl esters of vicinal diols are obtained by the reaction of alkenes with metal carboxylates [436]. Lead tetraacetate in acetic acid at 70 °C converts 1,2-dihydronaphthalene to rranj-l,2-diacetoxy-l,2,3,4-tetrahy-dronaphthalene in 72% yield [436]. The reaction is not always stereospecific. Cyclohexene treated with thallium triacetate gives a mixture of diastereomers in varying ratios, depending on reaction conditions, and byproducts as a result of rearrangements (equation 89) [411],... 

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