Figure 2.
Reagents and conditions: (a) acetic anhydride (1.0 eq.), pyridine, DCM, 52% b.r.s.m.; (b) acid chlorides, pyridine, DCM or DCE, 80–87%; (c) o-cresol, ZnCl2, POCl3, 70 °C, 69%; (d) SOCl2, reflux, then m-cresol, AlCl3, DCM, 0 °C to rt, 70%; (e) cyclohexanones, Zn, TiCl4, THF, reflux, 75–91%; (f) acetic anhydride, pyridine, DCM, 75–95%; (g) BBr3, DCM, − 78 °C to rt, 66%.