78984-36-8Relevant academic research and scientific papers
Preparation of six membered carocycles by aryl-tellurium mediated free-radical cyclisation
Barton,Dalko,Gero
, p. 4713 - 4716 (2007/10/02)
Radical cyclisation of various telluro-compounds was examined. Olefins conjugated to an electron withdrawing group, (7, 8, 9, 10, and 11) gave high yields of the corresponding six membered products. Non-activating olefin 23 gave the corresponding thiopyridyl derivative 24 as the only product. The photolysis, using oxime 18 as radicophile for the cyclisation, proceeded slowly at room temperature, and gave only a low yield of products 19 and 20.
A GENERAL PROCEDURE FOR THE SYNTHESIS OF METHYLTHIO-, METHYLSELENO- AND METHYLTELLURO-SUBSTITUTED AROMATIC COMPOUNDS
Engman, Lars,Hellberg, Jonas S. E.
, p. 357 - 366 (2007/10/02)
A one-pot procedure is described which allows the facile introduction of one or two methylchalcogeno groups into a variety of monobromo or dibromo aromatics.The bromo compounds were converted to their corresponding lithio derivatives by treatment with t-butyllithium in tetrahydrofuran at -78 deg C, and these derivatives were then treated, at ambient temperature with elemental sulfur, selenium, or tellurium.The resulting lithium thiolates, selenolates and tellurolates were finally methylated with methyl iodide to afford good yields (typically 50-80percent) of the various methylchalcogeno-substituted aromatic compounds.The procedure could not be used for the synthesis of ortho-disubstituted compounds, or for the simultaneous introduction of three methylchalcogeno groups.
