4-Nitroisoxazoles as nitroalkene heterodienes: diastereoselective synthesis of spiro tricyclic nitroso acetals by thermal reactions with ethyl vinyl ether
D. Giomi et al., 4-Nitroisoxazoles as nitroalkene heterodienes: diastereoselective synthesis of spiro tricyclic nitroso acetals by thermal reactions with ethyl vinyl ether, TETRAHEDRON, 57(19), 2001, pp. 4237-4242
A few 4-nitroisoxazoles were found to undergo highly diastereoselective per
icyclic homodomino processes with the title enol ether affording 1,6,9-trio
xa-5,9a-diazacyclopenta[d]indenes through bicyclic nitronates as hey interm
ediates. Formation of isoxazolooxepine systems is also reported together wi
th a domino reaction with the above reagent and methyl acrylate. Two X-ray
analyses of compounds 8 and 13 were carried out to firmly establish their s
tereochemistry. (C) 2001 Elsevier Science Ltd. All rights reserved.