4561-43-7Relevant articles and documents
Catalyst-Free Electrophilic Ring Expansion of N-Unprotected Aziridines with α-Oxoketenes to Efficient Access 2-Alkylidene-1,3-Oxazolidines
Chen, Xingpeng,Huang, Zhengshuo,Xu, Jiaxi
, p. 3098 - 3108 (2021/05/10)
2-(2-Oxoalkylidene)-1,3-oxazolidine derivatives were synthesized in good to excellent yields regiospecifically through the catalyst-free electrophilic ring expansion of N-unprotected aziridines and the ketene C=O double bond of α-oxoketenes, in situ generated from the microwave-assisted Wolff rearrangement of 2-diazo-1,3-diketones. The ring expansion predominantly underwent an SN1 process and the hydrogen bond decides the (E)-configuration of products. (Figure presented.).
Diamine-Tethered Bis(thiourea) Organocatalyst for Asymmetric Henry Reaction
Otevrel, Jan,Bobal, Pavel
, p. 8342 - 8358 (2017/08/23)
We have developed a novel multifunctional C2-symmetric biphenyl-based diamine-tethered bis(thiourea) organocatalyst, which was tested in the asymmetric Henry reaction. Under thoroughly optimized conditions, the catalyst provided exceptionally high yields and excellent enantioselectivities especially for electron-deficient aromatic and heterocyclic substrates. Due to a high affinity of the catalyst to silica gel, a simple chromatography-free nitroaldol isolation procedure was feasible. Preliminary kinetic and spectroscopic experiments were performed in order to complete the mechanistic picture of the organocatalyzed nitroaldolization process. Finally, the developed synthetic strategy was successfully applied to the catalytic enantioselective syntheses of enantiopure (S)-econazole and (R)-mirabegron a late-stage intermediate.
SYNTHESIS OF α-AMINO KETONE HYDROCHLORIDES VIA CHEMOSELECTIVE HYDROGENATION OF α-NITRO KETONES
Tamura, Rui,Oda, Daihei,Kurokawa, Hiroshi
, p. 5759 - 5762 (2007/10/02)
Chemoselective hydrogenation of various α-nitro ketones was accomplished with 5percent Pt sulfide on carbon as a catalyst to afford α-amino ketone hydrochlorides in good yields.
