79784-33-1Relevant academic research and scientific papers
Iridium-Catalyzed Asymmetric Hydrogenation of Unsaturated Piperazin-2-ones
Wang, Yanzhao,Liu, Yuanyuan,Li, Kun,Yang, Guoqiang,Zhang, Wanbin
supporting information, p. 1933 - 1941 (2017/06/09)
Two different iridium catalyst systems, generated from the ruthenocene-based phosphine-oxazoline ligand tBu-mono-RuPHOX or the diphosphine ligand BINAP, were developed for the asymmetric hydrogenation of 5,6-dihydropyrazin-2(1H)-ones, affording chiral piperazin-2-ones in good yields and with moderate to good ees. Different catalytic behaviors for the hydrogenation of these types of substrate were observed with these two catalyst systems. Our tBu-mono-RuPHOX ligand, which bears a ruthenocene scaffold with planar chirality, was found to be the best ligand for the [Ir(L)(COD)]BArF catalyst system, affording the desired products with up to 94% ee. (Figure presented.).
FLUORINE CONTAINING BIOACTIVE HETEROCYCLES PART III : SYNTHESIS OF SOME NEW FLUORINE CONTAINING PHENYLGLYOXALS AND 1,2,4-TRIAZINE DERIVATIVES
Joshi, Krishna C.,Dubey, Kalpana,Dandia, Anshu
, p. 1545 - 1553 (2007/10/02)
Some medicinally important new fluorine containing phenylglyoxals have been synthesized by selenium dioxide oxidation of appropriate fluorinated acetophenones and characterized by spectrum studies.The phenylglyoxals were treated with thiosemicarbazide to give corresponding thiosemicarbazones (III) which were cyclized, in situ, to yield 5-(fluorophenyl)-1,2,4-triazine-3(2H)-thiones.The 5-(4-fluorophenyl)-1,2,4-triazine-3-(2H)-thione (IV) undergoes nucleophilic displacement when refluxed with hydrazine hydrate to give corresponding 3-hydrazino-5-(4-fluorophenyl)-1,2,4-tria zine.The hydrazino derivative reacts with fluorinated 1,3-diketones, in glacial acetic acid yielding 5-(4-fluorophenyl)-3--1,2,4-triazines (VII).All synthesized compounds have been characterized on the basis of elemental analyses, ir, pmr and 19F nmr studies.
