stable crystalline phosphorus ylides are obtained in excellent yields from the 1:1:1 addition reactionbetween hydantoins or thiohydantoins and dialkyl acetylenedicarboxylates in the presence oftriphenylphosphine. these phosphoranes undergo smooth intramolecular wittig reaction followedby an electrocyclic ring opening to produce dialkyl (e)-2-(2,5-dihydro-5,5-diaryl-2-thioxo-1h-imidazol-4-yl)fum...

Comprehensive infiltration models can simultaneously describe transient and steady-state behaviors, therefore be applied to a range of experimental conditions. However, satisfactory model accuracy requires proper parameterization, including estimating the transition time from flow conditions (?crit). This study focused on improving estimation two parameters – ?crit second constant called used i...