An asymmetric Meerwein-Ponndorf-Verley (MPV) reduction of glyoxylates was for the first time accomplished via an N,N'-dioxide/Y(OTf)3complex with aluminium alkoxide and molecular sieves (MSs) as crucial additives. A variety of optically active α-hydroxyesters were obtained with excellent results. A possible reaction mechanism was proposed based on the experiments.
A highly regioselective N-1 and C-2 diacylation of 3-substituted indoles with arylglyoxal hydrates to afford N-1 and C-2 indolyl diketones in moderate to good yields is described. Notably, the control of regioselectivity is achieved by small changes in the Cu catalyst, additive and solvent. Importantly, the intermediates for N-1 and C-2 diacylation were detected and two plausible pathways were also
FeCl<sub>3</sub>or MeSO<sub>3</sub>H-promoted multicomponent reactions for facile synthesis of structurally diverse furan analogues
作者:Xiangqing Chang、Xiongfei Zhang、Zhiwei Chen
DOI:10.1039/c8ob00942b
日期:——
An intriguing conversion of arylglyoxal, cyclic dicarbonyl compounds and phenols to diverse furan analogues under FeCl3 or MeSO3H catalysis is reported. Utilizing this synthetic protocol, a variety of furan analogues could be easily obtained in moderate to good yields with different substituted patterns by varying the reaction medium. Atom-economical characteristics and mild conditions of this method
Synthesis of Furo[3,2-<i>c</i>
]coumarins via Lewis Acid-Mediated Multicomponent Tandem Reactions
作者:Xiangqing Chang、Piaopiao Zeng、Zhiwei Chen
DOI:10.1002/ejoc.201900987
日期:2019.10.17
Allyltrimethylsilane, arylglyoxal monohydrates, and cyclic 1,3‐dicarbonyl compounds afford furo[3,2‐c]coumarins through FeCl3 or ZnCl2‐mediated multicomponent tandem reactions in toluene. In the reaction, three components were used in one pot, and this method offers several advantages such as easily accessible starting materials, good functional group tolerance, and mild reaction conditions.
Copper-Assisted Synthesis of 2-Hydroxyphenyl-1,2-diones from Phenols and 2-Oxoaldehydes
作者:Narsaiah Battini、Satyanarayana Battula、Qazi Naveed Ahmed
DOI:10.1002/ejoc.201501423
日期:2016.2
An efficient copper(II)‐catalyzed protocol for the ortho‐functionalization of phenols is developed. This method tolerates a wide variety of 2‐oxoaldehydes and phenols and affords the corresponding 2‐hydroxyphenyl‐1,2‐diones in appreciable yields.