The reaction of thiobenzophenones (1) with phenyl[2-(trimethylsilyl)phenyl]iodonium trifluoromethanesulfonate (4) in the presence of tetrabutylammonium fluoride afforded the corresponding [4+2] cycloadducts, which are the first examples of thiobenzophenone-benzyne adducts. The reaction of thiopivalophenone (6) with benzyne prepared from 4 and tetrabutylammonium fluoride at room temperature gave [2+2]
The reaction of 2,2,4,4-tetramethyl-3-thioxocyclobutanone S-oxide with Lawesson reagent (L. R.) afforded the corresponding 1,2,4-trithiolane. Thiopivalophenone and thiopivalophenone S-oxides reacted with L. R. at rt to give the corresponding S-sulfide, which further reacted with thiones to afford the corresponding cis-1,2,4-trithiolanes.
2,2,4,4-四甲基-3-硫酮环丁酮 S-氧化物与 Lawesson 试剂(L. R. )反应,得到相应的 1,2,4-三硫环戊烷。硫代新戊酮和硫代新戊酮 S-氧化物与 L. R. 在常温下反应,得到相应的 S-硫化物,再与硫酮反应,得到相应的顺式-1,2,4-三硫环戊烷。
First Isolation of Thione-Propiolic Acid Adducts− Synthesis of Thiodioxenones
Treatment of adamantane-2-thione (1a) with propiolicacid (2a) afforded a novel type of cycloadduct, spiro[adamantane-2,2′-[1,3]oxathiin]-6-one (3a), in quantitative yield. The reaction proceeds through a concerted process, as was confirmed by kinetic analysis. Treatment of 1a with butynoic acid or phenylpropiolic acid gave the corresponding adducts regioselectively. Interestingly, only one isomer
Reaction of Thiopivalophenones with Benzyne. Formation of 2H-Benzo[b]thietes
作者:Kentaro Okuma、Kyoko Shiki、Kosei Shioji
DOI:10.1246/cl.1998.79
日期:1998.1
Reaction of thiopivalophenone with phenyl[2-(trimethylsilyl)phenyl]iodonium trifluoromethanesulfonate in the presence of tetrabutylammonium fluoride afforded the corresponding [2+2] cycloadduct, 2-tert-butyl-2-p-tolyl-2H-benzo[b]thiete, in 58% yield. On the other hand, reaction of thiopivalophenone with benzenediazonium 2-carboxylate gave 2-tert-butyl-2-p-tolyl-benzo[d][3,1]oxathiane-6-one in 82% yield