9-二茂铁基蒽与 1,4-苯醌的 Diels-Alder 加合物衍生的阳离子或阴离子的不同重排行为：开环或桨轮形成。

Different rearrangement behaviour of the cation or anion derived from the Diels-Alder adduct of 9-ferrocenylanthracene and 1,4-benzoquinone: ring-opening or paddlewheel formation.

机构信息

School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland.

出版信息

Chemistry. 2011 Dec 9;17(50):14241-7. doi: 10.1002/chem.201101854. Epub 2011 Nov 11.

DOI:10.1002/chem.201101854

PMID:22076754

Abstract

Prototropic rearrangement of the Diels-Alder adduct (3a) of 9-ferrocenylanthracene and 1,4-benzoquinone potentially furnishes 9-ferrocenyl-1,4-dihydroxytriptycene (3b) incorporating a C(2v) symmetrical paddlewheel moiety. However, reaction of 3a with HBF(4) unexpectedly yields instead 9-ferrocenyl-10-(2,5-dihydroxyphenyl)anthracene (4) via cleavage of the C9-C12 bond to generate initially a ferrocenyl-stabilized cation. Treatment of 3a with sodium hydride and iodomethane yields 1,4-dimethoxy-9-ferrocenyltriptycene (3c) in high yield but, surprisingly, also leads to fission of the C9-C12 bond resulting, after methylation, in the formation of 9-hydroxy-9-ferrocenyl-10-(2-hydroxy-5-methoxyphenyl)dihydroanthracene (12), which readily dehydrates on silica to form 9-ferrocenyl-10-(2-hydroxy-5-methoxyphenyl)anthracene (8). The X-ray crystal structures of 3a, 3c and 4 are reported.

摘要

9-二茂铁基蒽与 1,4-苯醌的 Diels-Alder 加合物（3a）的质子重排反应可能生成 9-二茂铁基-1,4-二羟基三并苯（3b），其中包含一个 C(2v)对称的桨轮部分。然而，3a 与 HBF(4)的反应出乎意料地生成了 9-二茂铁基-10-(2,5-二羟基苯基)蒽（4），通过 C9-C12 键的断裂生成了最初的二茂铁基稳定的阳离子。3a 与氢化钠和碘甲烷反应以高产率得到 1,4-二甲氧基-9-二茂铁基三并苯（3c），但令人惊讶的是，这也导致了 C9-C12 键的断裂，甲基化后形成 9-羟基-9-二茂铁基-10-(2-羟基-5-甲氧基苯基)二氢蒽（12），它在硅胶上容易脱水形成 9-二茂铁基-10-(2-羟基-5-甲氧基苯基)蒽（8）。报道了 3a、3c 和 4 的 X 射线晶体结构。