1376451-12-5Relevant academic research and scientific papers
Platinum(IV)-mediated nitrile-amidoxime coupling reactions: Insights into the mechanism for the generation of 1,2,4-oxadiazoles
Bolotin, Dmitrii S.,Bokach, Nadezhda A.,Haukka, Matti,Kukushkin, Vadim Yu
, p. 31 - 40 (2013/01/14)
We thank the Federal Targeted Program Scientific and Scientific- Pedagogical Personnel of the Innovative Russia in 2009-2013 (contract no. P1294 from 09/06/2010), the Russian Fund for Basic Research (grants nos. 11-03-00262 and 11-03-90417), the RAS Presidium Subprogram coordinated by academic N. T. Kuznetsov. We acknowledge Saint Petersburg State University for a research grant (2011-2013). Dr. P. S. Lobanov and Dr. S. A. Miltsov are thanked for stimulating discussions.
Platinum(IV)-mediated nitrile-amidoxime coupling reactions: Insights into the mechanism for the generation of 1,2,4-oxadiazoles
Bolotin, Dmitrii S.,Bokach, Nadezhda A.,Haukka, Matti,Kukushkin, Vadim Yu.
, p. 31 - 40 (2013/01/13)
The nucleophilic addition of amidoximes R'C(NH2)=NOH (4: R'=Me, 5: CH2Ph, 6: Ph) to coordinated nitriles in the platinum( IV) complexes trans-[PtCl4(RCN)2] (1: R=Et, 2: Ph, 3: NMe 2) proceeds in a 1:1 molar ratio and leads to the monoaddition products [PtCl4(RCN){HN=C(R)ONC(R')NH2}] (7: R/R': Et/CH2Ph, 8: Et/Ph, 9: NMe2/CH2Ph, 10: NMe 2/Ph). Meanwhile, if the nucleophilic addition proceeds in a 2:1 molar ratio the reaction gives the bisaddition species [PtCl4{HN=C(R) ONC(R')NH2}2] (11: R/R'=Et/Me, 12: Et/CH2Ph, 13: Et/Ph, 14: Ph/Ph, 15: NMe2/Me, 16: NMe2/CH 2Ph, 17: NMe2/Ph). All complexes 7-17 bear nitrogen-bound O-iminoacylated amidoxime groups. The addition of one equivalent of the corresponding amidoxime to each of 7-10 leads to 12, 13, 16, and 17, respectively. Complex [PtCl4(NCNMe2){HN=C(NMe 2)-ONC(Ph)NH2}] (10), when dissolved in MeNO2, gave mer-[PtCl3-{HN=C(NMe2)ONC(Ph)NHC(NMe 2)=NH}] (18) with the newly formed tridentate ligand derived from an unexpected coupling between two Me2NCN ligands and the N and the O centers of the amidoxime. The O-imidoylamidoxime compounds R'C(NH 2)=NOCR(=NH) (19-25) were liberated from the corresponding complexes 11-17 by treatment with excess NaCN and these metal-free species were characterized by 1H and 13C{1H} NMR spectroscopy. The conversion of 19-25 into the 3,5-substituted 1,2,4-oxadiazole compounds OaN=C(R')N= Cb(R)(a-b) (26: R/R'=Me/Et, 27: PhCH2/Et, 28: Ph/Et, 29: Ph/Ph, 30: Me/NMe 2, 31: PhCH2/NMe2, 32: Ph/NMe2) occurs at room temperature and the cyclization is promoted by strong acceptor substituents R'.
