167864-75-7Relevant academic research and scientific papers
Chemoselectivity and stereoselectivity of cyclisation of α-diazocarbonyls leading to oxygen and sulfur heterocycles catalysed by chiral rhodium copper catalysts
Ye, Tao,Garcia, Concepcion Fernandez,McKervey, M. Anthony
, p. 1373 - 1380 (2007/10/02)
Good levels of enantioselectivity have been achieved in intramiolecular C-H insertion reactions of α-diazocarbonyl compounds leading to six-membered oxygen heterocycles (chromanones) through the use of chiral rhodium(II) carboxylates as catalysts.Competition between C-H insertion and sigmatropic rearrangement, the latter leading to five-membered oxygen heterocycles (furanones), was observed with precursors containing a proximal O-allyl side chain.Whereas rhodium carboxylates produced C-H insertion products predominantly, a copper catalyst produced sigmatropic rearrangement products exclusively.A precursor with S-allyl side chain exhibited cyclisation via sigmatropic rearrangement with both copper and rhodium catalyst.
