Rhodium-Catalyzed Oxidative Cycloaddition of <i>N</i>
-<i>tert</i>
-Butoxycarbonylhydrazones with Alkynes for the Synthesis of Functionalized Pyrroles <i>via</i>
C(<i>sp</i>
<sup>3</sup>
)-H Bond Functionalization
作者:Chun-Ming Chan、Zhongyuan Zhou、Wing-Yiu Yu
DOI:10.1002/adsc.201600900
日期:2016.12.22
The reaction features a regioselective α‐imino alkyl C(sp3)−H bond functionalization resulting in selective formation of highlyfunctionalized NH‐free pyrroles. Our studies showed that utilizing the N‐tert‐butoxycarbonyl (N‐Boc) as the oxidizing directing group is critical for achieving the observed pyrrole formation versus the isoquinoline formation. To account for the pyrrole formation, we hypothesized
A C–H activation-based strategy has been developed for the synthesis of N-amino azaheterocycles. Rh(III)-catalyzed coupling of N-Boc hydrazones/N-Boc hydrazines with diazodiesters/diazoketoesters provides convenient access to synthetically and medicinally important compounds, N-amino isoquinolin-3-ones and N-amino indoles, by harnessing N-tert-butyloxycarbonyl (N-Boc) cleavage as an adaptable reactivity
Synthesis of 2,3-Benzodiazepines via Rh(III)-Catalyzed C–H Functionalization of <i>N</i>-Boc Hydrazones with Diazoketoesters
作者:Jie Wang、Lili Wang、Shan Guo、Shanke Zha、Jin Zhu
DOI:10.1021/acs.orglett.7b01642
日期:2017.7.7
An efficient Rh(III)-catalyzed C–H activation protocol has been developed for the synthesis of 2,3-benzodiazepines with use of N-Boc hydrazones and diazoketoesters as substrates. The reaction features retention of the C═N and N–N bonds and selective cleavage of the N-Boc moiety.
Rhodium(III)-Catalyzed Sequential Cyclization of <i>N</i>-Boc Hydrazones with Propargylic Monofluoroalkynes via C–H Activation/C–F Cleavage for the Synthesis of Spiro[cyclobutane-1,9′-indeno[1,2-<i>a</i>]indenes]
An effective rhodium(III) catalysis for the construction of valuable tetracyclic compounds is described herein. This dominoprocess involving the C–H activation/[3 + 2] annulation/intramolecular Friedel–Crafts reaction sequences of simple and readily available N-Boc hydrazones and propargylic monofluoroalkynes afforded fused tetracyclic spiro[cyclobutane-1,9′-indeno[1,2-a]indenes] in moderate to good