Synthesis of aryloxyaluminium hydrides and their conversion into aryloxyalumoxanes (ArOAlO)n.
The reaction of bulky phenols with H(3)Al x NMe(3) afforded the new primary phenoxyalanes Mes*OAlH(2) x NMe(3), 2 (Mes* = 2,4,6-(t)Bu(3)-C(6)H(2)-), 2,6-Dipp(2)C(6)H(3)OAlH(2) x NMe(3), 3 (Dipp = 2,6-(i)Pr(2)C(6)H(3)-), and 2,6-Trip(2)C(6)H(3)OAlH(2) x NMe(3), 4 (Trip = 2,4,6-(i)Pr(3)C(6)H(2)-) as colorless crystalline solids. Subsequent reactions of 2,6-(t)Bu(2)-4-MeC(6)H(2)OAlH(2) x NMe(3), 1, and 2 with oxygen sources such as (Me(2)HSi)(2)O or Me(2)SO gave the disiloxyalane 2,6-(t)Bu(2)-4-Me-C(6)H(2)OAl(OSiHMe(2))(2) x NMe(3), 5, and the alumoxane (Mes*OAlO.OSMe(2))(4), 6. The latter compound is a rare example of a species featuring an unsupported eight-membered (Al-O)(4) ring. The new compounds were characterized by (1)H and (13)C{(1)H} NMR and IR spectroscopy and elemental analyses, and compounds 3 and 6 were also characterized by single crystal X-ray diffraction.
Shekar
Sukesh
S
Department of Chemistry, Florida Institute of Technology, 150 West University Blvd., Melbourne, FL 32901, USA.
Taylor
Mamie M
MM
Twamley
Brendan
B
Wehmschulte
Rudolf J
RJ