87956-13-6Relevant academic research and scientific papers
Complementing Pyridine-2,6-bis(oxazoline) with Cyclometalated N-Heterocyclic Carbene for Asymmetric Ruthenium Catalysis
Li, Long,Han, Feng,Nie, Xin,Hong, Yubiao,Ivlev, Sergei,Meggers, Eric
, p. 12392 - 12395 (2020/06/10)
A strategy for expanding the utility of chiral pyridine-2,6-bis(oxazoline) (pybox) ligands for asymmetric transition metal catalysis is introduced by adding a bidentate ligand to modulate the electronic properties and asymmetric induction. Specifically, a ruthenium(II) pybox fragment is combined with a cyclometalated N-heterocyclic carbene (NHC) ligand to generate catalysts for enantioselective transition metal nitrenoid chemistry, including ring contraction to chiral 2H-azirines (up to 97 % ee with 2000 TON) and enantioselective C(sp3)?H aminations (up to 97 % ee with 50 TON).
Asymmetric Synthesis of 2H-Azirines with a Tetrasubstituted Stereocenter by Enantioselective Ring Contraction of Isoxazoles
Okamoto, Kazuhiro,Nanya, Atsushi,Eguchi, Akira,Ohe, Kouichi
, p. 1039 - 1043 (2018/01/26)
Highly strained 2H-azirines with a tetrasubstituted stereocenter were synthesized by the enantioselective isomerization of isoxazoles with a chiral diene–rhodium catalyst system. The effect of ligands and the coordination behavior support the proposed cat
Metal-Catalyzed Isomerization of 5-Heteroatom-Substituted Isoxazoles as a New Route to 2-Halo-2 H -azirines
Rostovskii, Nikolai V.,Agafonova, Anastasiya V.,Smetanin, Ilia A.,Novikov, Mikhail S.,Khlebnikov, Alexander F.,Ruvinskaya, Julia O.,Starova, Galina L.
, p. 4478 - 4488 (2017/09/26)
A convenient gram-scale method for the preparation of 2-halo-2 H -azirine-2-carboxylic acid esters, thioesters and amides via metal-catalyzed isomerization of 5-heteroatom-substituted 4-haloisoxazoles is developed. The formation of the esters and amides is efficiently catalyzed by Rh 2 (Piv) 4, while FeCl 2 ·4H 2 O is the catalyst of choice for the synthesis of the thioesters. In addition, rhodium catalysis is successfully applied in the synthesis of azirine-2-carboxylates from non-halogenated 5-alkoxyisoxazoles.
