Research on new synthetic routes about 221012-82-4

I hope my short article helps more people learn about this compound((R)-2,2′,6,6′-Tetramethoxy-4,4′-bis(diphenylphosphino)-3,3′-bipyridine)Reference of (R)-2,2′,6,6′-Tetramethoxy-4,4′-bis(diphenylphosphino)-3,3′-bipyridine. Apart from the compound(221012-82-4), you can read my other articles to know other related compounds.

The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Ru-catalyzed highly enantioselective hydrogenation of β-alkyl-substituted β-(acylamino)acrylates》. Authors are Wu, Jing; Chen, Xuanhua; Guo, Rongwei; Yeung, Chi-hung; Chan, Albert S. C..The article about the compound:(R)-2,2′,6,6′-Tetramethoxy-4,4′-bis(diphenylphosphino)-3,3′-bipyridinecas:221012-82-4,SMILESS:COC(C=C1P(C2=CC=CC=C2)C3=CC=CC=C3)=NC(OC)=C1C4=C(OC)N=C(OC)C=C4P(C5=CC=CC=C5)C6=CC=CC=C6).Reference of (R)-2,2′,6,6′-Tetramethoxy-4,4′-bis(diphenylphosphino)-3,3′-bipyridine. Through the article, more information about this compound (cas:221012-82-4) is conveyed.

β-Alkyl-substituted (E)-β-(acylamino)-acrylates R1C(AcNH):CHCO2R2 (R1 = Me, Et, EtCH2, Me2CH, Me3C; R2 = Me, Et) undergo enantioselective hydrogenation in the presence of the nonracemic bipyridyldiphosphine I (R = 3,5-Me2C6H3) and [RuCl2(benzene)]2 to provide β-aminoesters R1CH(NHAc)CH2CO2R2 in up to 99.7% ee. (Z)-β-(acylamino)-acrylates R1C(AcNH):CHCO2R2 (R1 = Me, Et, EtCH2, Me2CH, Me3C; R2 = Me, Et) undergo enantioselective hydrogenation in the presence of nonracemic bipyridyldiphosphine I (R = 3,5-Me2C6H3) and Rh(COD)2BF4 to provide β-aminoesters R1CH(NHAc)CH2CO2R2 in 57-82% ee. Hydrogenation does not occur in the presence of ruthenium or rhodium complexes of I (R = Ph, 4-MeC6H4, 3,5-Me2C6H3) in aprotic solvents; methanol is found to be the optimal solvent. Decreasing the hydrogen pressure increases the enantioselectivity marginally, with 4 atm. of hydrogen pressure being optimal. Ruthenium complexes of I give higher enantioselectivities for hydrogenation of (E)-β-aminoacrylates than the corresponding rhodium complexes; for the hydrogenation of (Z)-β-aminoacrylates, rhodium complexes of I give higher enantioselectivities than the corresponding ruthenium complexes. Variations in the electronic and steric properties of the dipyridylphosphine ligand, variation of the transition metal used, and variations in the enamine stereochem. influence the rate and enantioselectivity of the hydrogenation of β-(acylamino)acrylates.

I hope my short article helps more people learn about this compound((R)-2,2′,6,6′-Tetramethoxy-4,4′-bis(diphenylphosphino)-3,3′-bipyridine)Reference of (R)-2,2′,6,6′-Tetramethoxy-4,4′-bis(diphenylphosphino)-3,3′-bipyridine. Apart from the compound(221012-82-4), you can read my other articles to know other related compounds.

Reference:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider