The Ru(II)-Catalyzed Chelation-Assisted Arylation of C-H Bonds with Diaryliodonium Salts
The Ru(II)-Catalyzed Chelation-Assisted Arylation of C-H Bonds with Diaryliodonium Salts
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Ru(II) 催化二芳基碘鎓盐螯合辅助 C-H 键芳基化
DOI：
10.1002/ajoc.201300188
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
and N. Chatani
中科院分区：
文献类型：
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作者：
J. S. Ho;L. C. M. Castro;Y. Aihara;M. Tobisu;and N. Chatani
在过去的几十年里，腙作为合成有机化学中的通用试剂的效用已经众所周知。[1]特别是，使用手性腙的非对映选择性碳-碳键形成反应，如SAMP/RAMP [2]腙，[1 e]已被广泛研究并应用于各种天然产物和生物活性化合物的不对称全合成。最常用的制备腙的方法包括将羰基化合物如醛或酮与肼混合，其中形成等摩尔量的水作为副产物。合成此类衍生物的另一种原子经济的方法涉及将肼加成到炔上。该反应由Ti、[3] Rh、[4] Ir、[4] Au、[5]或Zn [6]络合物催化。由N-芳基肼衍生的产物通常会进行进一步的费歇尔吲哚环化，在某些情况下，需要随后添加到反应混合物中的锌盐[7]的辅助。[8，9]当使用末端炔作为底物时，在大多数已报道的催化体系中产生马尔可夫尼科夫型加合物。另一方面，只有少数报告的反马尔可夫尼科夫加氢肼化已经出现。Odom及其同事报道了苯乙炔与N，N-二取代肼的反应，导致产生腙，其与衍生自苯乙醛的那些相同。[3c]最近，Mountford及其同事报道了二苯基肼与芳基和三甲基甲硅烷基取代的炔的反马尔科夫加成反应。[3a]然而，前者在1-己炔的反应中得到马尔可夫尼科夫异构体，并且在后一种情况下，没有提及烷基取代的炔。本文报道了铑催化的末端炔与N-烷基肼和N，N-二烷基肼的反马氏氢肼化反应，得到醛亚胺型肼衍生物。据我们所知，这是第一个烷基取代的炔与肼以反马尔可夫方式反应的例子（方案1）。我们先前关于[TpRhACHTUNGTRENNUNG（C2 H4）2]/PPh 3催化的（Tp=三吡唑硼酸酯）末端炔的反马尔可夫氢胺化反应的报告[10]最初应用于1-十二炔与N-甲基肼的反应。在这种情况下，得到E-和Z-异构体的混合物（E/Z= 83/17）形式的1-十二烷叉基-2-甲基肼（1a），但产率低，为18%（表1，条目1）。虽然没有马-
The utility of hydrazones as versatile reagents in synthetic organic chemistry has been well-known for the last few decades.[1] In particular, diastereoselective carbon–carbon bond-forming reactions using chiral hydrazones, as represented by SAMP/RAMP [2] hydrazones,[1e] have been extensively studied and applied to the asymmetric total synthesis of a variety of natural products and biologically active compounds. The most commonly used method for the preparation of hydrazones involves mixing a carbonyl compound such as an aldehyde or a ketone, with a hydrazine, where an equimolar amount of water is formed as a byproduct. An alternative and atom-economical approach to the synthesis of such derivatives involves the addition of hydrazines to alkynes. This reaction is catalyzed by Ti,[3] Rh,[4] Ir,[4] Au,[5] or Zn [6] complexes. The products derived from N-arylhydrazines often undergo further Fischer indole cyclization, in some cases, assisted by a Zn salt [7] that is subsequently added to the reaction mixture.[8, 9] Markovnikov-type adducts are produced in most of reported catalytic systems when terminal alkynes were used as substrates. On the other hand, only a few reports of anti-Markovnikov hydrohydrazination have appeared. Odom and co-workers reported the reaction of phenylacetylene with N, N-disubstituted hydrazines leading to the production of hydrazones, which are the same as those derived from phenylacetaldehyde.[3c] Recently, Mountford and co-workers reported the addition of diphenylhydrazine to aryl-and trimethylsilyl-substituted alkynes in an anti-Markovnikov fashion.[3a] However, the former afforded the Markovnikov isomer in the reaction of 1-hexyne, and, in the latter case, no mention was made regarding alkyl-substituted alkynes. Herein, we report the rhodium-catalyzed anti-Markovnikov hydrohydrazination of terminal alkynes with N-alkyl-and N, N-dialkylhydrazines to give aldimine-type hydrazine derivatives. To the best of our knowledge, this is the first example of the reaction of alkyl-substituted alkynes with hydrazines in an anti-Markovnikov manner (Scheme 1).Our previous report on the [TpRhACHTUNGTRENNUNG (C2H4) 2]/PPh3-catalyzed (Tp= trispyrazolylborate) anti-Markovnikov hydroamination of terminal alkynes [10] was initially applied to the reaction of 1-dodecyne with N-methylhydrazine. In that case, 1-dodecylidene-2-methylhydrazine (1a) was obtained as a mixture of E-and Z-isomers (E/Z= 83/17), but in a low yield of 18%(Table 1, entry 1). Although no Mar-