Two organometallic fragments inclusioned in a 1,3-alternate calix[4]arene tetraphosphane: evidence for transition metal-arene interaction through the cavity.
The preparation of an 1,3-alternate calix[4]arene tetraphosphane ligand, 25,26,27,28-tetrakis{2-(diphenylphosphino)ethoxy}calix[4]arene (4), is described. Ligand 4 is obtained in four steps in 17% overall yield. Reaction of 4 with AgBF4 produced the encapsulated two silver complex [Ag2{(P,P,P,P)-tetraphencalix[4]arene}](BF4)2. The solid-state structure shows that the encapsulated silver undergoes a substantial pi-interaction by two opposite arene rings. Rhodation of 4 employing [Rh(cot)2]BF4 yielded the encapsulated complex with a bent coordination mode. Two organometallic fragments inclusioned inside a 1,3-alternate calix[4]arene tetraphosphane was also achieved by the reaction of 4 with [PtH(PPh3)2 (thf)]+. Full characterization includes X-ray structural studies of compounds 4-6.
Kim
Sanghoon
S
Department of Chemistry, Korea University, Jochiwon, Chungnam 339-700, Korea.
Kim
Jong Seung
JS
Kim
Sung Kuk
SK
Suh
Il-Hwan
IH
Kang
Sang Ook
SO
Ko
Jaejung
J