DMAP-Catalyzed [3 + 2] and [4 + 2] Cycloaddition Reactions between [60]Fullerene and Unmodified Morita–Baylis–Hillman Adducts in the Presence of Ac<sub>2</sub>O
作者:Hai-Tao Yang、Wen-Long Ren、Chun-Bao Miao、Chun-Ping Dong、Yang Yang、Hai-Tao Xi、Qi Meng、Yan Jiang、Xiao-Qiang Sun
DOI:10.1021/jo3025797
日期:2013.2.1
One-step DMAP-catalyzed [3 + 2] and [4 + 2] cycloaddition reactions between C60 and unmodified Morita–Baylis–Hillman adducts in the presence of Ac2O have been developed for the easy preparation of cyclopentene- and cyclohexene-fused [60]fullerene derivatives. When the MBH adducts bear an alkyl group, two different reaction pathways could be controlled selectively depending on the conditions.
The asymmetric synthesis of α-methylene-γ-butyrolactones via a tandem allylboration/lactonization approach was achieved using a chiral N,N′-dioxide/AlIII complex. The kinetic resolution of the allylboration intermediate via asymmetric lactonization was found to be a key aspect responsible for the success of this transformation. Stereodivergent syntheses and total syntheses of eupomatilones 2, 5 and
使用手性N , N ' -二氧化物/Al III络合物,通过串联烯丙基硼化/内酯化方法实现了 α-亚甲基-γ-丁内酯的不对称合成。发现烯丙基硼化中间体通过不对称内酯化的动力学拆分是该转化成功的关键因素。对Eupomatilones 2、5和6的立体发散合成和全合成证明了其合成实用性。
Efficient Baylis-Hillman Reaction via a 1,4-Diazabicyclo[2.2.2]octane-based Ionic Catalyst
作者:Yueqin Cai、Ye Liu、Guohua Gao
DOI:10.1007/s00706-007-0693-3
日期:2007.11
A novel ionic catalyst, 1-butyl-4-aza-1-azoniabicyclo [2.2.2] octane chloride based on 1,4-diazabicyclo[2.2.2] octane was synthesized and applied in the Baylis-Hillman reaction, which occurred readily at room temperature to afford the corresponding adducts in good yield. The ionic catalyst could be recycled for seven runs without diminution in its catalytic activity.