Ugi-post functionalization, from a single set of Ugi-adducts to two distinct heterocycles by microwave-assisted palladium-catalyzed cyclizations: tuning the reaction pathways by ligand switch
Linear amides, prepd. in one step by the Ugi four-component reaction, were converted to 3,4-dihydroquinoxalin-3-ones or to 2-(2-oxoindolin-1-yl)acetamides dependent on the catalytic conditions. While microwave irradn. was found to be determinant on the reaction efficiency, the choice of ligand diverged the reaction pathways. Heating a soln. of the linear amides in dioxane/MeCN (vol./vol. = 85/15) under microwave irradn. conditions in the presence of Pd(dba)2 (0.05 equiv) and Cs2CO3 (2 equiv), using XPhos as a supporting ligand, afforded the 3,4-dihydroquinoxalin-3-ones via an intramol. N-arylation of the secondary amide. On the other hand, using BINAP as ligand under otherwise identical conditions, intramol. alpha -CH arylation of tertiary amide occurred to furnish the oxindoles. [on SciFinder (R)]
2009
74
8
3109
3115
CAN 150:398491
28-17
Heterocyclic Compounds (More Than One Hetero Atom)
Institut de Chimie des Substances Naturelles,CNRS,Gif-sur-Yvette,Fr.
Journal
written in English.
3375-31-3 (Palladium diacetate); 32005-36-0 (Bis(dibenzylideneacetone)palladium); 72287-26-4 (Dichloro(diphenylphosphinoferrocene)palladium); 161265-03-8 (Xantphos); 251320-86-2; 564483-18-7 Role: CAT (Catalyst use), USES (Uses) (prepn. of benzopiperazinone derivs. via four-component Ugi addn. of iodoarylamines with carboxylic acids, aldehydes and isocyanides followed by palladium-XPhos-catalyzed heterocyclization under microwave irradn.); 75-98-9 (2,2-Dimethylpropanoic acid); 78-84-2 (2-Methylpropanal); 79-09-4 (Propanoic acid); 79-31-2 (2-Methylpropanoic acid); 95-51-2 (2-Chloroaniline); 104-53-0 (3-Phenylpropanal); 107-92-6 (Butanoic acid); 615-36-1 (2-Bromoaniline); 615-43-0 (2-Iodoaniline); 625-45-6 (2-Methoxyacetic acid); 772-15-6; 931-53-3 (Cyclohexylisocyanide); 7188-38-7 (tert-Butyl isocyanide); 10340-91-7 (Benzylisocyanide); 29289-13-2; 61272-76-2; 91394-63-7; 98991-09-4; 116632-14-5; 191348-14-8 Role: RCT (Reactant), RACT (Reactant or reagent) (prepn. of benzopiperazinone derivs. via four-component Ugi addn. of iodoarylamines with carboxylic acids, aldehydes and isocyanides followed by palladium-XPhos-catalyzed heterocyclization under microwave irradn.); 1139917-36-4P; 1139917-37-5P; 1139917-38-6P; 1139917-39-7P; 1139917-41-1P; 1139917-44-4P; 1139917-45-5P; 1139917-46-6P; 1139917-47-7P; 1139917-48-8P; 1139917-50-2P; 1139917-51-3P; 1139917-53-5P; 1139917-54-6P; 1139917-55-7P; 1139917-56-8P; 1139917-86-4P; 1139917-87-5P Role: RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (prepn. of benzopiperazinone derivs. via four-component Ugi addn. of iodoarylamines with carboxylic acids, aldehydes and isocyanides followed by palladium-XPhos-catalyzed heterocyclization under microwave irradn.); 1139917-58-0P; 1139917-60-4P; 1139917-62-6P; 1139917-63-7P; 1139917-64-8P; 1139917-65-9P; 1139917-66-0P; 1139917-67-1P; 1139917-68-2P; 1139917-70-6P; 1139917-71-7P; 1139917-72-8P; 1139917-73-9P; 1139917-75-1P Role: SPN (Synthetic preparation), PREP (Preparation) (prepn. of benzopiperazinone derivs. via four-component Ugi addn. of iodoarylamines with carboxylic acids, aldehydes and isocyanides followed by palladium-XPhos-catalyzed heterocyclization under microwave irradn.); 98327-87-8 (BINAP) Role: CAT (Catalyst use), USES (Uses) (prepn. of oxindole derivs. via palladium-BINAP-catalyzed heterocyclization of iodophenylaminocarboxamides under microwave irradn.); 1139917-76-2P; 1139917-78-4P; 1139917-80-8P; 1139917-81-9P; 1139917-82-0P; 1139917-83-1P; 1139917-84-2P; 1139917-85-3P Role: SPN (Synthetic preparation), PREP (Preparation) (prepn. of oxindole derivs. via palladium-BINAP-catalyzed heterocyclization of iodophenylaminocarboxamides under microwave irradn.)
REVIEWED
OTHER