Bischler-Napieralski reaction

reagent: pocl3
solvent: mecn, benzene, toluene, dcm, dmpu.
temp: rt - reflux
time: several hours.

not a nice and clean reaction. usually low yielding because of the strong acidic condition.
the product imine is sometimes not stable.

some milder conditions:
1. pph3/ccl4/reflux
2. Tf2O

a nice link:

http://www.organic-chemistry.org/namedreactions/bischler-napieralski-reaction.shtm