Oxidizing agents reagents studied

The parent indolo[2,3-fl]carbazole (1) has also been the subject of a study probing its reactivity toward oxidizing agents. One of the substrates involved, namely 85 (prepared from 1 and 2,5-dimethoxytetrahydrofuran in the presence of acid), was subjected to treatment with m-chloroperbenzoic acid, to give the dione 86 as the major product and a sensitive compound assigned the hydroxy structure 87. A cleaner reaction took place when 85 underwent oxidation with tert-butyl hydroperoxide assisted by VO(acac)2, to produce 86 exclusively in 86% yield. Likewise, A,N -dimethylindolo[2,3-fl]carbazole furnished the dione 88 on treatment with this combination of reagents (96J(X 413). 

Aluminophosphates (A1P04) were discovered in 198248 and a large amount of research has been directed towards the incorporation of various elements into the framework of these molecular sieves 49 A particular area of study is the oxidation of primary and secondary alcohols to the corresponding carbonyl compounds, which are useful synthetic intermediates. Traditionally, alcohol transformations are performed with stoichiometric chromium(VI) reagents.50 However, due to environmental problems associated with chromium-containing effluent, attention has focused on the use of chromium in conjunction with oxidizing agents such as tert-butyl hydroperoxide.51 Sheldon and co-workers... 

The title reagent, studied as an oxidizing agent for furans,104 converts tetraphenylpyrrole into a phosphorus complex, which is hydrolyzed by water to the hydrochloride of 2-hydroxypyrrolenine (32).63 The methyl ether (91) is obtained when the crude complex is treated with sodium methoxide. 

Also, a small amount of benzopinacol was isolated. The conjugate addition of Grignard reagents to sterically hindered benzophenones had been studied earlier [see, e.g.. Ref. 45], but it had never been detected for benzophenone itself. This is probably because of the instability of the dihydrobenzophenone, which at 80-90 C decomposes to form benzophenone and 2-methylpropane. In the presence of oxidizing agents, it undergoes aromatization to form 4-r-butylbenzophenone. Further studies in this field showed that with other substituted benzophenones, not only 1,2- and 1,6-addition took place, but, as expected, also 1,4-addition. This happened in particular with 4,4 -di-r-butyl- and 4,4 -dichlorobenzophenone. 

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