Yield:3382-63-6 88%

Reaction Conditions:

in isopropyl alcohol at 20 - 50; for 1.5 h;

Steps:

Preparation of Imine; Equipped a three necked 1 L flask with a mechanical stirrer, thermometer and an addition funnel. Added 480 mL of isopropanol, 144 g (1.18 moles) of p-hydroxybenzaldehyde (endothermic) and agitated the mixture while heating to a temperature of 50° C. Agitated the mixture at 50° C. for 15 min (making sure all the material was in solution), then added 114 mL (1.2 moles) of p-fluoroaniline slowly via the addition funnel (exothermic reaction). After the addition was complete, agitated the thick slurry for 1 hr at 50° C., cool to r.t. and agitated for 30 min. Filtered the product, washed the cake with 150 mL of isopropanol, dried the wet cake in a draft oven at 50° C. for 24 h or until dry to yield 222 g of the imine (88%);

References:

US2006/135755,2006,A1 Location in patent:Page/Page column 15-16