Novel oxidation of alkyl phenyl tellurides and telluroxides with meta-chloroperbenzoic acid: replacement of tellurium moiety by methoxy group accompanied by ring-contraction and phenyl migration
✍ Scribed by Sakae Uemura; Shin-ichi Fukuzawa
- Book ID
- 104221658
- Publisher
- Elsevier Science
- Year
- 1983
- Tongue
- French
- Weight
- 200 KB
- Volume
- 24
- Category
- Article
- ISSN
- 0040-4039
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✦ Synopsis
Oxidation of alkyl phenyl tellurides and telluroxides with meta-chloroperbenzoic acid in methanol at room temperature afforded the corresponding alkyl methyl ethers in high yields.
The reaction was accompanied by phenyl migration and ring-contraction respectively when applied to the compounds having phenyl group next to the tellurium moiety and to the methoxytelluration products of cyclic olefins.
Developement of synthetic methods based on tellurium chemistry is growing and of current interest, 1-3 though it is still far behind from that of fruitful organosulfur and organoselenium chemistry.
Recently a facile elimination of some telluroxides leading to olefins, allylic alcohols, and allylic ethers was reported.
4
We now find that a novel and facile carbon-tellurium bond fission occurs in tellurides and telluroxides to give alkyl methyl ethers when they are treated with m-chloroperbenzoic acid (MCPBA) in methanol. The reaction may provide a new method for the transformation of C-Te bond to C-O bond. Oxidation of alkyl phenyl tellurides (1.2) and telluroxides (3,4)4'5 with MCPBA in methanol at room temperature afforded the corresponding alkyl methyl ethers in good yields(Scheme I), none of methyl phenyl ethertanisole) being formed. Generally, 3-5 and l-2 equivalents of MCPBA to organotellurium compounds were necessary in the cases of tellurides and telluroxides, respectively. The expected tellurones, [PhTe(0)2Rl, one of which having been prepared by the NaI04 oxidation of 4-methoxyphenyl dodecyl telluroxide, 6 were not isolated at