24837-19-2Relevant academic research and scientific papers
Chemoselectivity control: Gold(I)-catalyzed synthesis of 6,7-dihydrobenzofuran-4(5H)-ones and benzofurans from 1-(alkynyl)-7- oxabicyclo[4.1.0]heptan-2-ones
Wang, Tao,Shi, Shuai,Vilhelmsen, Mie Hojer,Zhang, Tuo,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
supporting information, p. 12512 - 12516 (2013/09/23)
New and chemoselective gold(I)-catalyzed transformations of 1-(arylethynyl)-7-oxabicyclo[4.1.0]- heptan-2-ones were developed. Two completely different products - 6,7-dihydrobenzofuran-4(5H)-ones and benzofurans - could be obtained from the same starting material. The selectivity is determined by the ligand of the gold catalyst: triphenylphosphine delivers 6,7-dihydrobenzofuran-4(5H)-ones, and 1,3-bis(diisopropylphenyl)imidazol-2- ylidene leads to benzofurans. Eleven examples of each case are provided. The mechanistic suggestions for the pathways to both product types are supported by isotope labeling experiments. Complete chemoselectivity control of gold(I)-catalyzed transformations of 1-(arylethynyl)-7-oxabicyclo[4.1.0]heptan- 2-ones, which can be achieved by changing the ligand of the gold catalyst, allows two different products to be obtained from the same starting material, namely, 6,7-dihydrobenzofuran-4(5H)-ones and benzofurans (see scheme), both of which are potent building blocks for synthetic chemistry. IPr: 1,3-bis(diisopropylphenyl)imidazol-2-ylidene. Copyright
