Barrelenes electrophilic additions

When the anisole ligand is substituted at C4, Michael addition still occurs para to the methoxy group provided that the electrophile is sterically unhindered. When 3-butyn-2-one is used as the Michael acceptor and care is taken to eliminate all proton sources, the initially formed boron enolate (70) closes to form an rq -barrelene complex (71 see Fig. 15), which eliminates ammonia to give the tetraammine analog (72) [46]. 

---

See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ , ]

---