Remote controlled Haller–Bauer ring opening of bicyclo[2.2.2]octenones
摘要:
A new, unprecedented case of the Haller-Bauer reaction in bicyclo[2.2.2]octenones, easily obtained from the Diels-Alder reaction, provides effective and stereocontrolled access to highly substituted cyclohexene derivatives. (C) 2001 Elsevier Science Ltd. All rights reserved.
stereoslective inverse-electron-demand Diels–Alderreactions of masked o-benzoquinones (MOBs) 1a–1h derived from the corresponding 2-methoxyphenols 2a–2h with benzyl vinyl ether, dihydrofuran and styrene to afford the highly functionalized bicyclo[2.2.2]octenone derivatives are described. The MOBs having electron-deficient substituents were found to undergo more facile Diels–Alder cycloadditions with these dienophiles