| Abstrakt: |
Two synthetic routes leading to 4-(1′-azoniabicyclo[2.2.2]octanyl)-2,2-diphenyl-2-borata-1,3-dioxa-1,2,3,4-tetrahydronaphthalene, 5, are described. Crystals of the product are orthorhombic, a = 18.099(2), b = 9.729(2), c = 12.113(2) Å, Z = 4, space group Pca21. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.034 and Rw = 0.037 for 1421 reflections with I > 3σ(F2). Compound 5represents the first structurally characterized crystalline adduct of a trialkylamine to a carbonyl compound in which the newly formed C—N bond is acyclic. The adduct is stabilized by the neighboring Lewis acid diphenylboryloxyaryl moiety. Bond distances involving the boron atom ((aryl)O—B = 1.515(4), (alkyl)O—B = 1.508(4), and C(phenyl)—B = 1.613(5) and 1.623(5) Å) represent relatively strong overall binding of the O,O-chelating ligand to the diphenylboron moiety. |
