Ring Expansion and Rearrangements of Rhodium(II) Azavinyl Carbenes
作者:Nicklas Selander、Brady T. Worrell、Valery V. Fokin
DOI:10.1002/anie.201207820
日期:2012.12.21
regioselective, and convergent method for the ring expansion and rearrangement of 1‐sulfonyl‐1,2,3‐triazoles under rhodium(II)‐catalyzed conditions is described. These denitrogenative reactions form substituted enaminone and olefin‐based products (see scheme). The enaminone products can be further functionalized to give various heterocycles and ketonederivatives, thus rendering the sulfonyl triazole traceless
扩展空间:描述了一种在铑 (II) 催化条件下进行 1-磺酰基-1,2,3-三唑环扩展和重排的有效、区域选择性和收敛方法。这些脱氮反应形成取代的烯胺酮和基于烯烃的产物(参见方案)。烯胺酮产物可以进一步官能化,得到各种杂环和酮衍生物,从而使磺酰三唑变得无痕。
Synthesis of α-Amino Ketones from Terminal Alkynes via Rhodium-Catalyzed Denitrogenative Hydration of <i>N</i>-Sulfonyl-1,2,3-triazoles
N-Sulfonyl-1,2,3-triazoles react with water in the presence of a rhodium catalyst to produce alpha-amino ketones in high yield. An intermediary alpha-imino rhodium(II) carbenoid undergoes insertion into the O-H bond of water. This transformation formally achieves 1,2-aminohydroxylation of terminal alkynes in a regioselective fashion when combined with the copper(I)-catalyzed 1,3-dipolar cycloaddition with N-sulfonyl azides.
Copper and Rhodium Relay Catalysis for Selective Access to <i>cis</i>-2,3-Dihydroazepines
作者:You Li、Han Luo、Zongyuan Tang、Yingzi Li、Luan Du、Xiaolan Xin、Shanshan Li、Baosheng Li
DOI:10.1021/acs.orglett.1c02262
日期:2021.8.20
access synthetically challenging cis-2,3-dihydroazepines is reported. The reaction starts with readily available dienals, alkynes, and sulfonyl azides as the substrates and employs copper and rhodium as relay catalysts. Key steps include a copper-catalyzed reaction between an alkyne and a sulfonyl azide to form a triazole intermediate. The subsequent activation of this triazole intermediate by a rhodium