Stereocontrolled Photodimerization with Congested 1,8-Bis(4′-anilino)naphthalene Templates
作者:Marwan W. Ghosn、Christian Wolf
DOI:10.1021/jo101547w
日期:2010.10.1
transformation gave 1,8-bis(3′-methyl-4′-anilino)naphthalene, 16, and 1,8-bis(4′-anilino)naphthalene, 21, in 65% and 90% overall yield, respectively. These congested compounds exhibit two cofacial aniline rings that favor a proximate, parallel arrangement of covalently attached cinnamoyl units suitable for stereoselective photodimerization. The [2 + 2]cycloaddition was found to proceed with high yield and
将1,8-二卤代萘与4-甲氧基-3-甲基苯基硼酸或4-乙酰氨基苯硼酸进行铃木交叉偶联,然后进行官能团转化,得到1,8-双(3'-甲基-4'-苯胺基)萘,16,和1,8-双(4'-苯胺基)萘21的总收率分别为65%和90%。这些拥挤的化合物显示出两个有利于立体选择性光二聚化的共价连接的肉桂酰基单元近端,平行排列的苯胺环表面。发现[2 + 2]环加成以高收率进行并且排他地形成顺式,反式,顺式-环丁烷-1,2-二羧酸。与肉桂酰氯和模板21形成酰胺然后进行光化学二聚和酸性水解,以总收率的69%生成10%的β-精氨酸。在EDC,UV辐射和裂解作用下,将21和(E)-3-(3,4-二甲基苯基)丙烯酸偶联,得到顺,反,顺-3,4-双(3,4-二甲基苯基)环丁烷-1,2-二羧酸26,收率60%。在这两种情况下,模板都是定量回收的。