The diisobutylaluminum hydride (DIBAL-H)-promoted benzocyclization, recently developed by this group, was adopted for the synthesis of a natural product containing a 9,10-dihydrophenanthrene skeleton to demonstrate its synthetic utility. One of the extracts from the roots of Salvia hydrangea DC. ex Bentham (Lamiaceae), a 20-norabietane derivative, was selected as the target molecule. The key step forming the 9,10-dihydrophenanthrene skeleton was achieved by the DIBAL-H-promoted cyclization of a silylated 1,3-dien-5-yne easily accessible from a substituted α-tetralone.

中文翻译：

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二异丁基氢化铝促进的甲硅烷基化1，3-二烯-5-炔的环化反应：在全合成20-壬二烷衍生物中的应用

该小组最近开发的由二异丁基氢化铝（DIBAL-H）促进的苯并环化反应被用于合成含有9,10-二氢菲骨架的天然产物，以证明其合成用途。丹参绣球DC的根中的一种提取物。选择一种20-norabietane衍生物的前Bentham（唇形科）作为目标分子。形成9,10-二氢菲骨架的关键步骤是通过DIBAL-H促进的硅烷化1，3-二烯-5-炔基的环化反应而实现的，该环化反应可轻松地从取代的α-四氢萘酮中获得。