Reações de contração de anel promovidas por sais de tálio(III)

Abstract

Recebido em 16/3/99; aceito em 9/6/99 RING CONTRACTION REACTIONS PROMOTED BY THALLIUM(III) SALTS. Thallium(III) salts promote a number of different reactions useful in organic synthesis. In this paper, the ring contraction of ketones and olefins, mediated by thallium(III) salts, is exhaustively reviewed.

Indatraline: Synthesis and Effect on the Motor Activity of Wistar Rats

“…The oxidation of 1,2-dihydronaphthalene 5 with iodine(III) [ 20 , 22 , 31 , 32 , 33 , 34 ] or with thallium(III) [ 30 , 31 , 33 , 35 , 36 , 37 , 38 , 39 , 40 ] in MeOH furnished the indane 4 , the naphthalene 7 and the addition product 8 , depending on the reaction conditions ( Table 1 ). With 0.9 equiv.…”

Hypervalent Iodine–Mediated Ring Contraction Reactions

“…The authors proposed that the reactive species in this reaction is PhI(OMe) 2 or PhI(OH) 2 , which would be generated by the reaction of iodosobenzene with MeOH or H 2 O, respectively. Then, an electrophilic addition of iodine(III) to the double bond would give the carbocation 45, that would lead to the adduct 46 after addition of a molecule of solvent.…”

(+)- and (−)-Mutisianthol: First Total Synthesis, Absolute Configuration, and Antitumor Activity

“…Thus, mutisianthol is one of several examples of a natural product whose structure was misassigned and later on corrected by chemical synthesis . In the past decade, several approaches were investigated for the synthesis of indanes through the ring contraction of readily available 1,2-dihydronaphthalenes mediated by thallium(III) or by iodine(III), including applications in total synthesis. ,, One of the targets was (±)-mutisianthol, which was synthesized in 12 steps and in 8% yield from 2-methylanisole…”