2851-68-5Relevant articles and documents
Carbohydrate-based spiro bis(isoxazolines): synthesis and evaluation in asymmetric catalysis
Goyard, David,Telligmann, Susanne M.,Goux-Henry, Catherine,Boysen, Mike M.K.,Framery, Eric,Gueyrard, David,Vidal, Sébastien
supporting information; experimental part, p. 374 - 377 (2010/03/24)
Two carbohydrate-based spiro bis(isoxazolines) were synthesized via 1,3-dipolar cycloaddition from peracetylated methylene exo-glucal and the corresponding bis(arylnitrile oxide). The bis(cycloadducts) were then evaluated as ligands for enantioselective catalytic reactions. The Pd-catalyzed Tsuji-Trost reaction between a malonate and an allylic acetate did not provide good results. The poor conversion observed can be attributed to the rearrangement of the ligand in the reaction mixture to afford the corresponding ring-opened isoxazole which has been characterized. Both ligands were also evaluated in Cu(I)-catalyzed asymmetric imine alkynylation and afforded the product in good yield and modest enantioselectivity.
Multiple Cycloadditive macrocyclization: An Efficient Method for Crown Ether-Type Cyclophanes, Bis-Calix[4]arenes and Silamacrocycles
Kim, Byeang Hyean,Jeong, Eun Jeong,Hwang, Gil Tae,Venkatesan, Natarajan
, p. 2191 - 2202 (2007/10/03)
Macrocycles constitute a broad spectrum of compounds, which play a significant role in host-guest supramolecular chemistry. We have rationally designed an efficient novel synthetic method to synthesize different types of artificial receptive macrocycles containing isoxazoline or isoxazole ring systems. This method involves multiple (double, triple or quadrupole) cycloadditions between bifunctional dipoles and bifunctional dipolarophiles. We have presented our synthetic results to show the ease with which this one-pot synthetic method can be extended to synthesize different types of macrocycles such as cyclophanes, bis-calix[4]arenes and silamacrocycles. Hence, with appropriate combination of bifunctional dipoles and bifunctional dipolarophiles, the ring size of macrocycles could be controlled. This multiple cycloadditive macrocyclization will be a useful arsenal for the synthesis of various macrocycles.
