Total Synthesis of <i>e</i><i>nt</i>-Dihydrocorynantheol by Using a Proline-Catalyzed Asymmetric Addition Reaction
作者:Takashi Itoh、Masashi Yokoya、Keiko Miyauchi、Kazuhiro Nagata、Akio Ohsawa
DOI:10.1021/ol0530575
日期:2006.4.1
[reaction: see text] 9-Tosyl-3,4-dihydro-beta-carboline reacted with 3-ethyl-3-buten-2-one in the presence of (S)-proline to give (3R,12bR)-3-ethyl-12-tosyl-3,4,6,7,8,9,10,11,12,12b-decahydro-1H-indolo[2,3-a]qui nolizin-2-one in complete enantio- and diastereoselectivity. The compound thus obtained was readily transformed to ent-dihydrocorynantheol in three steps.
[反应:参见正文]在(S)-脯氨酸存在下,9-Tosyl-3,4-dihydro-beta-carboline与3-ethyl-3-buten-2-one反应生成(3R,12bR)-3 -乙基-12-甲苯磺酰基-3,4,6,7,8,9,10,11,12,12b-十氢-1H-吲哚并[2,3-a] qui nolizin-2-one完全对映体和非对映选择性。这样得到的化合物可以通过三个步骤容易地转化为对二氢七氢萘酚。