62056-77-3Relevant academic research and scientific papers
Microwave-Assisted Ruthenium- and Rhodium-Catalyzed Couplings of α-Amino Acid Ester-Derived Phosphinamides with Alkynes
Li, Xue-Hong,Gong, Jun-Fang,Song, Mao-Ping
supporting information, (2021/12/23)
Two different types of new phosphinamide α-amino ester derivatives have been prepared in moderate to high yields via ruthenium(II) and rhodium(III)-catalyzed ortho-C?H functionalization under microwave irradiation. Specifically, the ortho-alkenylated phosphinamides were produced through coupling of phosphinamides containing an α-substituted or α,α-disubstituted α-amino ester with internal alkynes under ruthenium catalysis. In contrast, Ru and the more effective Rh-catalyzed coupling of the α-unsubstituted glycine ester phosphinamide with alkynes resulted in formation of oxidative annulation products, phosphaisoquinolin-1-ones. The developed methods feature the use of easily accessible starting materials, short reaction time, exclusive E-stereoselectivity (for ortho-alkenylation) and good functional group tolerance. The alkenylation reaction was readily scaled up to gram scale. Furthermore, the obtained alkenylated phosphinamide could be transformed into P-containing dipeptides through hydrolysis of the ester group in the catalysis product and subsequent condensation with an α-amino ester.
PHOSPHOROAMIDE COMPOUND, METHOD FOR PRODUCING THE SAME, LIGAND, COMPLEX, CATALYST, AND METHOD FOR PRODUCING OPTICALLY ACTIVE ALCOHOL
-
Page/Page column 27, (2009/12/23)
Disclosed is a method for highly efficiently obtaining an optically active alcohol from a carbonyl compound highly enantioselectively. Also disclosed is a ligand used in such a method. Specifically, an optically active alcohol is obtained by reacting a ca
Application of Diphenylphosphinic Carboxylic Mixed Anhydrides to Peptide Synthesis.
Ramage, Robert,Hopton, David,Parrott, Maxwell J.,Richardson, Reginald S.,Kenner, George W.,Moore, Geoffrey A.
, p. 461 - 470 (2007/10/02)
Diphenylphosphinic carboxylic mixed anhydrides formed in situ from Nα-protected amino acids and diphenylphosphinic chloride have been critically evaluated in peptide synthesis.Wherever possible, 32.4 MHz 31P n.m.r. spectroscopy has been employed to follow the rates of both mixed anhydride formation and aminolysis.
Phosphinamides: A New Class of Amino Protecting Groups in Peptide Synthesis
Ramage, Robert,Hopton, David,Parrott, Maxwell J.,Kenner, George W.,Moore, Geoffrey A.
, p. 1357 - 1370 (2007/10/02)
Nα-Diphenylphosphinyl protected α-amino acids have been prepared from the corresponding methyl or benzyl esters using diphenylphosphinic chloride-N-methylmorpholine followed by mild alkaline hydrolysis or catalytic hydrogenolysis, respectively.The suitability of these derivatives for use in amide bond forming reactions and their stability during the customary manipulations of peptide synthesis have been exhaustively examined.Acid-catalysed removal of the diphenylphosphinyl group has also been studied, with the aid of 32.4 MHz 32P n.m.r. spectroscopy, and compatability of cleavage with tryptophan and methionine residues - in the absence of scavengers - has been demonstrated by the synthesis of the partially protected C-terminal tetrapeptide of gastrin, Cl(1-)H2(1+)Trp-Met-Asp(Ot-Bu)-PheNH2.
