Silver-Promoted Direct Phosphorylation of Bulky C(sp2)-H Bond to Build Fully Substituted β-Phosphonodehydroamino Acids
A general and practical cross-dehydrogenative coupling protocol between readily available trisubstituted α,β-dehydro α-amino carboxylic esters and H-phosphites is described. This C(sp2)-H phosphorylation reaction proceeds with absolute Z-selectivity promoted by silver salt in a radical relay manner. The bulky tetrasubstituted β-phosphonodehydroamino acids were obtained in grams and added new modules to the toolkit for peptide modifications.
Benzylidene-oxazolones as photoswitches: Photochemistry and theoretical calculations
The photophysics and photochemistry of a family of compounds proposed as efficient molecular photoswitches is presented. The effect of different light sources, substituents and solvents in the photostationary state has been explored. A detailed mechanisti
Funes-Ardoiz, Ignacio,Blanco-Lomas, Marina,Campos, Pedro J.,Sampedro, Diego
p. 9766 - 9771
(2013/10/22)
Facile synthesis of 4-arylidene-5-imidazolinones as synthetic analogs of fluorescent protein chromophore
A facile and effective synthesis for a wide variety of 4-arylidene-5- imidazolinone derivatives was developed. 4-Arylidene-5-oxazolinones were prepared by Erlenmeyer azlactone synthesis from N-acylglycines and arylaldehydes. The ring-opening reactions of the 4-arylidene-5-oxazolinones with primary amines afforded 2-acylamino-3-arylacrylamides in excellent yields. A new dehydrative cyclization of the 2-acylamino-3-arylacrylamides in pyridine under reflux furnished the corresponding 4-arylidene-5-imidazolinones in good yields.