THE REACTIONS OF t-BUTYL PERBENZOATE AND OLEFINS—A STEREOSPECIFIC REACTION¹

Recent progress in the trifluoromethylation of alkenes with Togni's reagents

“…Reaction of Togni's reagents with a copper catalyst generates a CF 3 radical (Scheme 2), 23,24 followed by radical addition and single-electron oxidation to give intermediate C. 26 Subsequent trapping of the carbocation C with a nucleophile leads to the desired product D. It is assumed that trifluoromethylation of olefin substrate E might be achieved using a copper-based strategy involving the generation of an allylic radical and a subsequent CF 3 transfer (Scheme 3, Path A). [27][28][29] Alternatively, if Togni's reagent 1 could be used as an electrophilic CF 3 ·equivalent, the final product F may be generated through an atom transfer radical addition type pathway (Scheme 3, Path B). 30 Finally, an electrophilic trifluoromethylation proceeding via a cationic intermediate may also be viable (Scheme 3, Path C).…”

Reactions of t-Butyl Peresters, XVIII Peroxyester Reaction of t-Butyl N,N-Dimethylperoxyamidate

“…In the thermal peroxyester reaction of 1 (R = N(CH3)2) with cyclohexene, the higher boiling products were 3,3'-dicyclohexenyl (5) in 40% yield, cyclohex-l-en-3-yl N,N-dimethylamidate (6) in 20% yield, as detei mined by gas chromatography.…”

“…In preliminary experiments, peroxyamidate I (R = N(CÜ3)2) was allowed to react under the conditions of the peroxyester reaction [1,3,[5][6][7] with a number of substrates 2, i.e., cyclohexene, cumene, tetrahydrofuran, diethyl ether, dimethylformamide, which are known to give preparatively useful results with i-butyl peroxyacetate or J-butjd peroxybenzoate [1][2][3]. Attention was focused on the disappearance of the infrared carbonyl absorption of the peroxyamidate 1, R = N(CH3)2, at v ~ 1740 cm -1 and the appearance of the infrared carbonyl absorption of the products at v ca 1720 cm -1 , and the extent of gas evolution.…”

<b>Synthesis of 7-dehydrocholesterol through hexacarbonyl molybdenum catalyzed elimination reaction</b>

“…Choleterol-3,7-diacetate formation is also reported by using electrochemical oxidation of cholesterol [12]. Karash [13,14] procedure of allylic esterification using copper catalyst has taken much more attention throughout the history for the synthesis of allylic acetates. Different experimental conditions are optimized to make the reaction simple and productive.…”