A new one-pot Synthesis of 3-(1,2,3,4-tetrahydroisoquinolin-1-yl)- isoquinolin-1(2H)-ones by DEAD-promoted oxidative Ugi/Wittig reaction was developed. The sequential reactions of (2-carboxybenzyl)triphenylphosphonium salts, isocyanides and N-aryl-1,2,3,4-tetrahydroisoquinolines produced 3-(1,2,3,4-tetrahydroisoquinolin-1-yl)- isoquinolin-1(2H)-ones in moderate to good overall yields in the presence of DEAD and Et3N.
AbstractA one-pot protocol for the synthesis of 5-(1,2,3,4-tetrahydroisoquinolin-1-yl)-1,3,4-oxadiazoles via DEAD-mediated oxidative Ugi/aza-Wittig reaction has been developed. The reaction of (N-isocyanimine)triphenylphosphorane, carboxylic acids, and N-aryl-1,2,3,4-tetrahydroisoquinolines produced polysubstituted 5-(1,2,3,4-tetrahydroisoquinolin-1-yl)-1,3,4-oxadiazoles directly in good yields in the presence of DEAD as an oxidant.
7-Borylindoles undergo a one-pot oxidative hydrolysis-oxidative cleavage process to give o-amidophenols, that in turn undergo facile cyclisation to give 4-acylbenzoxazoles.
Tandem oxidation–Wittig reaction using nanocrystalline barium manganate (BaMnO4); an improved one-pot protocol