Bischler-Napieralski

(POCl3)







Examples:


Example 1



To a solution of the SM (76.0 g, 0.354 mol) in DCM (2.5 L) at 15 C was added POCl3 (155 g, 1.01 mol). After addition, the reaction mixture was heated to reflux for 3 h. The mixture was cooled to RT and concentrated in vacuo. To the residue was added H2O (1.5 L), toluene (1.5 L), and 20% NaOH (500 mL). The mixture was refluxed for 1 h, then cooled to RT. The mixture was diluted with EtOAc, washed with H2O, then brine. The org layer was dried (Na2SO4), concentrated, and purified by silica gel column chromatography (10:1 PE/EtOAc) to provide the product as a brown oil. [58.5 g, 94%]


[Patent Reference: WO2016014463, page 94, (6.7 MB)]