Pd-Catalyzed Ring Opening of Oxa- and Azabicyclic Alkenes with Aryl and Vinyl Halides: Efficient Entry to 2-Substituted 1,2-Dihydro-1-naphthols and 2-Substituted 1-Naphthols
作者:Chi-Li Chen、Stephen F. Martin
DOI:10.1021/jo060299p
日期:2006.6.1
1,2-dihydronaphthols in good to excellent yields. These reactions occurred under very mild conditions with a variety of aryl halides bearing electron-withdrawing or -donating groups. Similarly, a 7-azabenzonorbornadiene substituted with an electron-withdrawing group on the nitrogen atom underwent facile ring-opening reaction with aryl halides to provide cis-2-substitued (1,2-dihydro-1-naphthyl)carbamates
已经开发出一种有效合成2-取代的1,2-二氢-1-萘和2-取代的1-萘的方法,该方法包括依次用钯催化氧杂双环烯烃与芳基和乙烯基卤化物的开环,然后用IBX氧化。在序列的第一步中,将Pd(OAc)2,PPh 3,Zn和PMP的混合物用干DMF催化7-氧杂苯并降冰片二烯与芳基和乙烯基卤化物的开环反应,得到相应的顺式-2-取代的1,2-二氢萘类具有良好至极好的收率。这些反应在非常温和的条件下与各种带有吸电子或供电子基团的芳基卤化物发生。类似地,在氮原子上被吸电子基团取代的7-氮杂苯并降冰片二烯与芳基卤化物进行开环反应,从而以优异的产率提供顺式-2-取代的(1,2-二氢-1-萘基)氨基甲酸酯。使用IBX对中间体1,2-二氢-1-萘进行氧化,得到相应的2-取代的1-萘,收率良好至优异。