Synthesis of thiiranes through direct sulfur transfer to cycloalkenes in the thermolysis of a thiophene endoperoxide
摘要:
Thiophene endoperoxide 2, which was prepared by photo-oxygenation of thiophene 1, transfers a sulfur atom to form thiiranes when thermolysed in the presence of cycloalkenes, an unexpectedly efficient process which can be catalysed by the cobalt-tetraphenylporphine complex.
Triphenylphosphine reduction of thiophene endoperoxides: nucleophilic attack on sulfur versus biphilic insertion into the peroxide bond
作者:Waldemar Adam、Stephan Weinkötz
DOI:10.1016/0040-4039(95)01553-1
日期:1995.10
The thiopheneendoperoxide 2a, obtained by photooxygenation of thiophene 1a, led with triphenylphosphine to the furan 3a and betaine 4, while the 5-phenyl derivative 2b produced quantitatively furan 3b; two independent reaction pathways are proposed which entail nucleophilicattack on sulfur by triphenylphophine to afford entrione 5a and betaine 4 and biphilicinsertion into the peroxidebond to generate