A direct amidation of carboxylicacids with tertiary amines could be carried out in the presence of the Ph3P–I2 activator. With an appropriate reagent addition sequence, a range of carboxylicacids including aliphatic, allylic, and aromatic acids could be converted into their corresponding tertiary amides under mild conditions without requirement of metal catalysis.
Chemical‐Reductant‐Free Electrochemical Deuteration Reaction using Deuterium Oxide
作者:Xu Liu、Ruoyu Liu、Jiaxing Qiu、Xu Cheng、Guigen Li
DOI:10.1002/anie.202005765
日期:2020.8.10
We report a method for the electrochemical deuteration of α,β‐unsaturated carbonyl compounds under catalyst‐ and external‐reductant‐free conditions, with deuteration rates as high as 99 % and yields up to 91 % in 2 h. The use of graphite felt for both the cathode and the anode was key to ensuring chemoselectivity and high deuterium incorporation under neutral conditions without the need for an external
novel tandem metal-free oxidative aryl migration/C–Cbond-cleavage reaction, mediated by hypervalent iodine reagent, has been discovered. The presented transformation provided straightforward access to important α-ketoamide and α-ketoester derivatives from readily available acrylic derivatives via a concerted process of 1,2-aryl shift concomitant with C–C bond cleavage.
Ligand regulation for manganese-catalyzed enantioselective epoxidation of olefins without acid
作者:Daqian Xu、Qiangsheng Sun、Jin Lin、Wei Sun
DOI:10.1039/d0cc04440g
日期:——
been developed for enabling acid-free asymmetric epoxidation of olefins with tert-butyl hydroperoxide as the oxidant. A variety of olefins that are well-matched in size with the ligand pocket can be transformed to epoxides with excellent enantioselectivities. The smaller ligand pocket is also beneficial to the enantioselective epoxidation of simple olefins. Cryospray ionization mass spectrometry experiments
已经开发了带有L-脯氨酸衍生的N 4配体的新型锰催化剂,其能够使用叔丁基氢过氧化物作为氧化剂实现烯烃的无酸不对称环氧化。大小与配位体袋完全匹配的各种烯烃可以转化为具有出色对映选择性的环氧化物。较小的配体口袋也有利于简单烯烃的对映选择性环氧化。低温喷雾电离质谱实验表明,Mn IV O物种可作为活性环氧化物种。
Asymmetric Epoxidation of Olefins with H<sub>2</sub>O<sub>2</sub>Catalyzed by a Bioinspired Aminopyridine N4 Iron Complex
作者:Wenfang Wang、Qiangsheng Sun、Daqian Xu、Chungu Xia、Wei Sun
DOI:10.1002/cctc.201601293
日期:2017.2.6
An iron complex with a chiral aminopyridine N4 ligand bearing strong electron‐donating and bulky morpholine groups on the ligand is synthesized and characterized. The iron complex serves to efficiently catalyze the asymmetric epoxidation of various olefins by employing aqueous hydrogenperoxide as the green oxidant, providing the corresponding epoxides in good to excellent yields and enantioselectivities