Synthesis of α-Amino Ketones from Terminal Alkynes via Rhodium-Catalyzed Denitrogenative Hydration of N-Sulfonyl-1,2,3-triazoles
摘要:
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.
1-Sulfonyl-1,2,3-triazoles, readily prepared from terminal alkynes and sulfonylazides, react with allenes in the presence of a nickel(0) catalyst to produce the corresponding isopyrroles. The initially produced isopyrroles are further converted to a wide range of polysubstituted pyrroles through double bond transposition and Alder-ene reactions.
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
<i>N</i>
<sup>2</sup>
-Selective Autocatalytic Ditriazolylation Reactions of Cyclopropenones and Tropone with <i>N</i>
<sup>1</sup>
-Sulfonyl-1,2,3-triazoles
作者:Long-Hai Li、Yu Jiang、Jian Hao、Yin Wei、Min Shi
DOI:10.1002/adsc.201700936
日期:2017.10.4
N2‐Selective autocatalytic ditriazolylation reactions of cyclopropenones and tropone with N1‐sulfonyl‐1,2,3‐triazoles are reported for the first time. In contrast to previous methods for preparing N2‐substituted bis(1,2,3‐triazolyl) compounds, the present reaction achieved ditriazolylation in one step under simple and user‐friendly conditions with a wide substrate scope. A plausible mechanism has been