81928-69-0Relevant articles and documents
Ruthenium-catalyzed umpolung carboxylation of hydrazones with CO2
Yan, Si-Shun,Zhu, Lei,Ye, Jian-Heng,Zhang, Zhen,Huang, He,Zeng, Huiying,Li, Chao-Jun,Lan, Yu,Yu, Da-Gang
, p. 4873 - 4878 (2018)
The first ruthenium-catalyzed umpolung carboxylation of hydrazones with CO2 to generate important aryl acetic acids is reported. Besides aldehyde hydrazones, a variety of ketone hydrazones, which have not been successfully applied in previous umpolung reactions with other reactive electrophiles, also show high reactivity and selectivity under mild conditions. Moreover, this operationally simple protocol features good functional group tolerance, is readily scalable, and offers easy derivation of important structures, including bioactive felbinac and adiphenine. Computational studies reveal that this umpolung reaction proceeds through the generation of a Ru-nitrenoid followed by concerted [4 + 2] cycloaddition with CO2.
Highly para-Selective C?H Alkylation of Benzene Derivatives with 2,2,2-Trifluoroethyl α-Aryl-α-Diazoesters
Ma, Ben,Chu, Zhaowei,Huang, Ben,Liu, Zhenli,Liu, Lu,Zhang, Junliang
supporting information, p. 2749 - 2753 (2017/02/26)
Compared to the most popular directing-group-assisted strategy, the “undirected” strategy for C?H bond functionalization represents a more flexible but more challenging approach. Reported herein is a gold-catalyzed highly site-selective C(sp2)?H alkylation of unactivated arenes with 2,2,2-trifluoroethyl α-aryl-α-diazoesters. This protocol demonstrates that high site-selective C?H bond functionalization can be achieved without the assistance of a directing group. In this transformation, both the gold catalyst and trifluoroethyl group on the ester of the diazo compound play vital roles for achieving the chemo- and regioselectivity.
COBALT-CATALYZED SYNTHESIS OF α-ARYLPROPIONIC AND DIARYLACETIC ACIDS
Francalanci, F.,Gardano, A.,Foa, M.
, p. 277 - 282 (2007/10/02)
The cobalt-catalyzed carbonylation of ArCH(R)X (R=CH3, C6H5; X=Cl, Br) in alcoholic solvents under atmospheric pressure of CO is reported.Selective, high yield synthesis of the corresponding acids ArCH(R)COOH can be achieved within a very narrow range of experimental conditions by controlling kinetically the reversible interconversion of intermediate aryl and alkylcobalt complexes.The important roles of the base and of the alcoholic medium are briefly discussed.