One-Pot Sequential N-Heterocyclic Carbene/Rhodium(III) Catalysis: Synthesis of Fused Polycyclic Isocoumarins
作者:So Won Youn、Huen Ji Yoo
DOI:10.1002/adsc.201700072
日期:2017.7.3
A one‐pot sequential N‐heterocyclic carbene–rhodium (NHC‐Rh) catalysis is described, demonstrating the compatibility of NHC and Rh catalysts. N‐Heterocyclic carbene‐catalyzedaerobicoxidation of benzaldehydes and subsequent rhodium(III)‐catalyzedoxidative coupling/annulation with multiple bonds enabled the formation of two C–O bonds and one C–C bond in a single pot. This operationally easy, one‐pot
Ru-Catalyzed Decarboxylative Annulations of α-Keto Acids with Internal Alkynes: Dual Roles of COOH as Directing Group and Leaving Group
作者:Hui Tan、Hongji Li、Jiawang Wang、Lei Wang
DOI:10.1002/chem.201405715
日期:2015.1.26
Carboxylic acid serving as both directing and leavinggroup was discovered in Ru‐catalyzed decarboxylativeannulations of α‐keto acids with alkynes. The well‐established protocol showed high functional group tolerance, which provided an efficient and alternative route to the coumarone backbone.
Cp*Co(III)-Catalyzed Annulation of Carboxylic Acids with Alkynes
作者:Rajib Mandal、Basker Sundararaju
DOI:10.1021/acs.orglett.7b00801
日期:2017.5.19
A new procedure for oxidative coupling of aromatic and acrylic acids with alkynes has been developed using abundant, nontoxic, and air stable Cp*Co(III) catalyst. The coupling involves initial cyclometalation via weak chelation-assisted C–H bond activation followed by alkyne coordination, insertion, and reductive elimination leading to diverse isocoumarins (α-pyranones) in good yields under mild conditions
Rhodium(III)‐Catalyzed, CH Activated Annulation to Form Isocoumarins and
<i>α</i>
‐Pyrones using the ON Bond as an Internal Oxidant
作者:Xing Guang Li、Kai Liu、Gang Zou、Pei Nian Liu
DOI:10.1002/adsc.201400200
日期:2014.5.5
A mild, efficient and regioselective CHactivation‐based intermolecular redox‐neutral annulation of O‐benzoylhydroxylamines and internal alkynes has been achieved. The protocol employs an ONbond as the internaloxidant and leads to isocoumarins and α‐pyrones.
Rhodium(III)-Catalyzed C–H Activation/Alkyne Annulation by Weak Coordination of Peresters with O–O Bond as an Internal Oxidant
作者:Jiayu Mo、Lianhui Wang、Xiuling Cui
DOI:10.1021/acs.orglett.5b02291
日期:2015.10.16
A redox-economic strategy has been developed, involved in an efficient Rh(III)-catalyzed oxidative C–H activation and alkyneannulation with perester as the oxidizing directing group. In this process, the cleavage of an oxidizing O–O bond as an internal oxidant is described for the first time. This reaction could be carried out under mild conditions and exhibits excellent regioselectivity and wide